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How to let 2 split screen apps run at top performance?
I noticed that on my Xiaomi 11i with the Snapdragon 888 processor, it is supposed to be one of the current top Android phones, with 8 cores and that only the Apple A14 Bionic has slightly higher performance than it.
However, if I run two Pokemon Go using its Dual App split screen, then I noticed, if we look inside a gym, and a Pokemon (Venonat or Exeggutor) is swinging left and right, then every few seconds, on the top or bottom screen, the Pokemon would have a slight 0.2 second pause, so both apps are choppy every few seconds.
If I use the app Activity Monitor, right after I boot up the phone so that no other app is running, I did see that every 6 to 10 seconds, all the cores of the processors would ramped up to 100%, so it looks like it is doing some work in the background.
I noticed if I run one single instance of Pokemon Go, then it is smoother.
But my question is, how can 8 cores not able to handle some slowing animating graphics. If anything, the swinging left and right repeatedly can even be "set it and forget it" -- everything done by the GPU (Adreno 660).
So trying to solve it, I tried to tap the Version number of the system for a few times and went to Developer's Options, and from there, I set the background app to be: Running only 1 process at a time.  So that should mean I have 7 cores running now for the 2 apps on screen? But after rebooting the phone and trying again, the same issue was still there.  Is there a way to make it able to take 2 cores (or 3 cores) for each app, or just make them run at top performance and let any background process run with the remaining 2 cores?  Or another way is, if there is a way to set the background processes only use up to 50% of the cores, so the main apps can always have 8 cores to use.
Update: an insight to finding a solution: I noticed if we tap on a Pokemon and try to catch it, the Pokemon, if it is a flying Pokemon with their wings constantly flapping in the dual app, has really smooth animation and there is no tiny pauses ever.  It may appear that when we look inside of a gym, usually six Pokemon are shown inside, so if both apps are looking inside of a gym, there can be 12 Pokemon moving inside.  Even if 10 Pokemon have tiny movements only and two Pokemon have more apparent movements, it seemed it was possible that 12 threads were used, and so if there are 12 threads and 8 cores, maybe that's the reason that there can be tiny pauses.  I am not sure if we can change the Settings on the phone to solve this, as these movements are very lightweight.

You don't have "8 cores" you have 1+3+4 cores, so you have three different categories of cores each of them with different speed and power consumption (extended BIG-little concept). So some of your cores are designed to be slow bet very battery saving.

so can app one take core 1 & 2, and app two take core 3 & 4, and let the other cores handle other background processes?

Apps don't "take" cores, the Linux part of Android does the process scheduling and assigns processes to cores based on it's internal rules (don't know how the scheduling rules for an Snapdragon 888 look). And that you can't run two games at the same time may simply be because it has never been tested. Usually fore-ground apps assume they don't have to share resources. But other reasons in the Android graphics system may also have an influence on this. I don't know Pokemon Go but if it allows to change graphics settings e.g. to reduce quality do so.

I mean, running split screen app has been possible since Android 7... and Xiaomi has this dual app mode before that.  I do have a OnePlus Nord N10 and Samsung A32 and they have no Xiaomi Dual app on them so I had to use the Android 7 split screen with Pokemon Go and the Galaxy store version, and similar situation is happening. That's what I mean. The OS should be smart enough to know 2 apps are running and dedicate one or two cores to them so that they run smoothly


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How does Audio metadata works?
I have an Android device on which I want to pair phone/laptop and play songs:

When I pair my phone and I play a song, the song's metadata is displayed on the Android device.

When I pair my laptop to the Android device and I play the same songs, the metadata is not displayed.

Why? Any explanation?

I forgot to write what type of device you pair with your Android in first case, I assume you have some Bluetooth headphone? In the second case you pair the phone with your computer. What OS runs on the computer? What Bluetooth profiles are supported by the computer (I would assume that a computer does not provide the BT headphone/audio profile)?

Additionally shown meta data are shown by the player app. Therefore you should edit your question and add the name and Play Store link of audio player app you use.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

sort: votes


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How do I create a separate vendor partition?
I recently got an android phone running AOSP Android 5.1 Lollipop. I want to upgrade its software to higher android version, probably 9.0 as per the phone's capacity. But for that, I need treble support in the phone. And for that, I need to create a vendor partition. Here is a tutorial I found on XDA.
Link
This guide is focused on MI3/MI4 devices and the resource ROM mentioned in it is also for MI3/MI4 devices. I think they may not work on my phone. The phone with me is of Micromax Canvas model. So please guide me through this. Thanks.

You can't make a device support treble by simply creating a vendor partition. Better search for the newest custom ROM for your device and use that.

No new ROM available for this model. But even if I can't support treble by creating a vendor partition, please tell me how to create a vendor partition. And if the above method is applicable for other devices too.

Please read including all comments. Working on the partition table is the easiest way to brick your device: https://android.stackexchange.com/questions/237263/resize-system-partition-on-galaxy-note-3-sm-n9005

Looks serious. Thanks for all these resources. I will try my best not to do it.

Use parted or gdisk (or its variant) tools to create partition as you would do on any Linux system. Here's a quick example to use sgdisk: https://android.stackexchange.com/a/220042/218526. Bear in mind that any such command could be the last communication you've with your device. Partitioning is something which must be done when you know what you are doing, not by copying commands from support forums.

Thanks for the information Irfan Latif. I know that wrong partitioning can be the worst nightmare for a person with a phone. But, I still wish to try it out on my experiment phone as I have its stock rom and flash tool to restore original os if anything goes wrong.

Be aware that stock ROM and flash tool might not be enough to restore a device bricked due to partitioning went wrong: Can I flash Android on device with overwritten mmcblk0?.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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My phone is charging my MacBook over USB C, and not showing up as an adb device. Is there a fix?
Sorry in advance if this is a duplicate, I couldn't find a solution to this exact problem posted anywhere.
I'm using Unity on macOS and I am trying to build for Android. I'm running into an issue where my development phone (it's a Galaxy A5 2017) will start charging my MacBook when I plug it in and will not show up as an adb device.
What I've done so far is:

Enable USB debugging on my phone
Install android-sdk and android-platform-tools through homebrew
Install openjdk@8 through homebrew (this resolved an issue where the sdk required java 8)
Attempt to switch the USB mode on the phone from 'Charge connected device' to 'Transfer files'
Switch USB ports

Trying to switch USB modes on the phone does not seem to work, it will close the dialog when selecting 'Transfer files' but when I check in the notification shade it will still be set to 'Charge connected device'. I also tried checking if the phone showed up over adb, but unfortunately adb devices returns an empty list.
Potentially useful information: I have built this exact Unity project to this exact phone successfully from my Windows desktop with this USB C to C cable, but I need to be able to do this from my MacBook.
I am using:

Unity 2021.1.4f
macOS Big Sur 11.4
Android 8.0.0

My question is, how can I prevent my phone from trying to charge the Mac? How can I get it to show up as an adb device so I can build to it from Unity?
Edit: alecxs suggested another question as a possible solution but this did not work for me either. In USB debugging, the USB mode is still set to MTP file transfer when this issue occurs. Changing it to something else and back unfortunately does not resolve the issue.
Edit 2: looks like this is a problem with macOS. I came across this article that mentioned for Samsung phones you need to use Smart Switch. I downloaded it for macOS, but it warned me that until further notice they do not support Big Sur as their system extension has not been approved. There is a temporary workaround mentioned in the warning here, but it is a bit involved, requiring you to disable SIP. For now this seems like the only solution. Since I know the root of the issue, I will mark this question as solved.

May be this is the way to tell you how Apple thinks of Android? "As power bank they might be usable but as smartphone they are not comparable to our unmatched iPhone", sorry SCNR. To be serious when it works with a Windows PC but not with a MAC then most likely the device is not the problem and you need an expert in MAC configuration...

Does this answer your question? Plugging phone into laptop charges laptop instead of phone

@alecxs Thanks for the suggestion, I tried checking the USB setting in the Debugging Options but it was already set to MTP while the phone is plugged in, and changing it to something else and back doesn't seem to work either.

I believe I've found the issue, I added an edit to the original post. Looks like this is a problem with macOS. I came across this article that mentioned for Samsung phones you need to use Smart Switch. I downloaded it for macOS, but it warned me that until further notice they do not support Big Sur as their system extension has not been approved. There is a temporary workaround mentioned in the warning that can be found here, but it is a bit involved, requiring you to disable SIP. For now this seems like the only solution until Apple approves the extension.


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Pixel 4a : adb detects device but fastboot command doesn't work
This is a self answered question that is different and may save hours of frustration to somebody
Related questions but none that helped

ADB detects my device but fastboot doesn't
Yureka fastboot not detected in LINUX, but adb detects device
ADB detects but, fastboot does not detect device in windows 10
adb can find device but fastboot cannot
fastboot not showing device (nokia 2.1 ) but adb works fine
adb devices show phone in debug mod but not in fastboot mod
Fastboot detects phone in the fastboot mode but not when phone is on

My situation

After more than 6 months I thought of updating security patches on my Pixel 4a Android 11 (stock)  and root it again.

I uninstalled Magisk , applied OTA update , extracted boot image and patched it with magisk (see this). All smooth

Problem
I needed to run fastboot flash boot patched.img to root the device. But when I run the command response is <waiting for any device>, which was strange since adb devices shows device serial.
Things tried, without any luck

Updated adb on Lint Minux, it was latest

Switched to Windows 10 and updated

Andrew in chat pointed to an XDA thread, which was better covered by Izzy here How do I get my device detected by ADB on Linux?. Added udev rule but then no dice.

Firelord in chat suggested it could be plugdev issue so tried the solution mentioned in this Stack Overflow question adb devices => no permissions (user in plugdev group; are your udev rules wrong?), though the problem wasn't similar

Multiple cables , rebooting Android, Windows, Linux when I was at a loss to figure out

Variations of fastboot like fastboot flash boot_a patched.img, fastboot flash boot --slot all patched.img and sudo fastboot devices

Finally, the solution ....

I have now idea why this worked. Before running fastboot commands rebooted device in download mode:

adb reboot bootloader to get into fastboot
fastboot devices shows device serial
fastboot flash boot patched.img works :)
fastboot reboot to get back to normal device state
Device is rooted and I see su permission requests

Note: Some devices of LG and Samsung lack fastboot functionality.


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Lenovo S5 storage filled with invisible files
I have a Lenovo S5 with 64gb internal storage. I had this problem for a while now, so i really need some help.
Any file manager that I can find sums up all my files and aplications at under 20 gb, however i only have 3 gb free.
About 40 gb are filled with invisible/unfindable files. I looked online for answers many time, and I tried using "Android terminal emulator" with the command "df -h" and got this result, can anyone make something of it?

Starting point: our storage tag wiki has some pointers on how to find out what "ate" your storage.

There is one simple answer: You as the use and your apps don't have access to those files. Therefore those files are "invisible" to you. That is the Android storage design.

So how do I delete those files (or are they actually part of apps, but not registered so?)

basically yes, not all apps will delete it's files on uninstall. factory reset will solve this

Does this answer your question? What Is Using Up My Storage/Data on Android Phone?


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Broken OTP SMS on Xiaomi
I have a Xiaomi Mi Max 3 phone. Recently, I changed my app for SMS to "Messenger for messages" from "Messaging" that is, I assume, the app from Xiaomi.
For the login of Dropbox or a Credit Card, I usually receive an SMS from a foreign country (I am living in Israel) and the message, instead of e.g. a six-digit number, is this:

For SMS from my country, e.g. to enter in gov. sites with an SMS code, it works fine.
After reading in the comments about the possibility that the problem is linked to the app, I deleted Messenger for messages, and the messages I receive are the same. Here are sample SMSes from Dropbox:

?,§ieKAF§IKAHKAf?ÅWK'såW¥2;#KC+s$Φövv.ùRü.Ψw.Å
?,§ieKAF§IKAHKAf?ÅWK'såW¥Φ+3#;s$Φövv.ùRü.Ψw.Å
?,§ieKAF§IKAHKAf?ÅWK'såW¥Φ+KΓs$Φövv.ùRü.Ψw.Å
?,§ieKAF§IKAHKAf?ÅWK'såW¥2;K#Cs$Φövv.ùRü.Ψw.Å

When the expected SMS is like

Your security code is [6-digit code]. Happy Dropboxing!

Screenshot of the SMSes
And here is a sample SMS from Amazon:

?PiiaguÜÜBÄCu§ÑÑF§Ä§B§F§d§ΣQQaΦsrl$a¤#Qekm¤æ-GìKìM§ΩΛ$ÄCu§Ñu¡(KÑiCiSmKAHKAFQCÑOKÄKÑiAHKAZ§iAHKA¿CggKAHKA(¥Y¡ΦΘÑ¡$aaksKuAfkeAXKAXSKÑA¿§keAda§ÑIeKÑ

When the expected SMS is like

[6-digit code] is your Amazon OTP. Do not share it with anyone.

I came back to the regular SMS app for the Xiaomi phone and the problem wasn't solved. I contacted my telephone operator and they say that if an SMS is received, it's not a problem related to them. They have nothing to do with the content of the messages.  I contacted the support team of Dropbox, and they weren't able up to day to understand what is the problem. I am very surprised. I have also uninstalled and reinstalled the dual identification and the problem remained.
Maybe relevant:

My new phone is a Xiaomi Poco F3, I use the Google SMS App and the problem is the same.
I missed to acknowledge that I am living in Israel, my phone operator is we4G.
I still have the problem with the bank CIC that sends SMS from France, Dropbox, and Amazon, not with Google and GitHub.
Dropbox and Amazon weren't able to explain the phenomenon, neither my phone operator.

My question is what can I do to repair it?

Have you ever received a valid SMS before? If so, is it in English, or foreign (e.g. Hebrew) language?

@Andrew of course, along many years.

A message in English

Was there a reason you changed the SMS app? May be it is just a bug in the SMS app. There are other good SMS/messenger apps available, I would recommend e.g. Signal as messenger+SMS app.

@Robert despite I came back to the first app, the default app for this phone, the problem remained.

I can think of 2 possibilities: 1) wrong encoding on the app's side (unlikely after using more than 1 apps), or 2) an issue from the telephone operator (what might be called as "SMS relay"). FWIW, I had answered a similar issue regarding this: Receiving Chinese blocks of texts in the Messaging app, but still not sure if this is the same case...

Very good post! @Andrew For encoding changing I need some knowledge. I will try.

I just noticed the SMS from Dropbox has a pattern, so looks like the problem is on the encoding. Could you copy and paste one of the contents from the old SMS? I want to experiment with it.

Every sma from the bank is repeatedly the aime, and for Amazon equally. It's expected to be a 6 digit number


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How to change the compression and format settings of images taken in 8k+ 64MP on my Samsung Galaxy S20+ 5G
The Camera App natively supports 64MP and I have read that my phone (Samsung Galaxy S20+ 5G) may be able to go even higher.
I'm taking lots of pictures in 64MP and it's great, but I've noticed an issue.
The images appear to be compressed with visible compression artifacts in the lossy jpeg format.
I'd much prefer that that they are stored losslessly when taken and later I can deal with how I want to compress/handle them.
I have not yet found an app or setting that can do this.
Most of the apps and settings I've used to get a RAW image generally work, but none have preserved the capacity to take pictures in 64MP, instead they apply to 4k, which is not what I'm interested in especially.
I've tried the Camera App's Pro Mode, Open Camera, CameraMX and Lightroom. I even tried using a special build of Google's Camera App for my phone that I got from XDA Developers. And CameraMX just crashes at start.

I looked at the specs of the Galaxy S20+ 5G and I only see two 12 MP, a telephoto 64 MP and a depth camera. If the stock Samsung camera app isn't giving you any larger RAW sizes, it is doubtful such a thing is possible (only Samsung has access to camera drivers and such). See related questions in comments to: pixel binning vs higher individual pixel size

Thanks. I originally noticed that one of my images showed a visible grid structure when zoomed in. I assumed this had to do with jpeg compression. Now I look at my 8k images and I don't see that same structure. Interesting...


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Is there a way to make the battery level easier to see on some Android phones such as Xiaomi?
I looked at the battery level on Samsung A32 and it was easy to look at, but on Xiaomi it looks like this:

Is there a way to make it easier to look at?  Right now I have to go to Settings -> Battery to get a better idea.  We might be able to change the theme to make it easier to look at, but it'd be a overkill to change the theme for the whole phone just for the battery level.
For example, down below the status line, it says
4:41                             Clear 21°C
Friday May 28

in big fonts.  Is it possible to add the battery level display there?

Battery, time and such elements in the status bar are decided by system UI properties and can't be changed on isolation. Two options I know of - one is rooted means to change the appearance, second is battery monitoring apps that add their own icon which may be more legible but you still end up displaying the system battery, which can be quite ugly. Rooting is the preferred option if nothing offered by OS is preferred option

What is for you "easier to see"? For myself I prefer the batter percent value or are you referring to the battery color (white on light blue background)? In the latter case have you tried to change the background image to one that has a dark area in the upper part?

I can't really tell if it is 36% vs 96% or 26%... the percentage background is not that apparent


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Is there there a way to download media from any android app
I'm not talking about popular applications like Youtube, Facebook or Instagram...
Let's say there's an android app called 'bla' and there are videos in it just like youtube and not showing the url...
What I'm asking is... Is there any way to download these videos directly from the app(using an xposed module or wtever..) or to find the urls of the videos(so I can download them from pc)...
Any help would be appreciated..

No need for root even if you can export files directly from the app. Some helpers for that would be Save a copy, Phone Saver or Send to SD card.

If the app is a streaming app without download (offline) function then videos are never saved as file and thus can not be retrieved by apps mentioned by Izzy. For streaming apps there is no universal way.

In addition to what Robert said, if the app is using encryption on media files then the files are useless to the user.

Thank you guys for replying... yeah its a streaming app☹... is there any way to get the streaming link even.. then I can try something from pc.. I tried using packet capture to grab the streaming link... But the problem is packet capture use vpn and this app doesnt allow ips from other countries I guess(It's not opening when packet capture is running)... Please let me know.. if somebody knows a trick to get the link..


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Redmi 4X (santoni): Abruptly shuts down just before booting into OS
Here's a TL;DR -
I can't boot into my OS,phone shuts down after being in boot screen for some time but I can boot into fastboot and recovery. I flashed another custom ROM after formatting my device but it won't change the state of affairs.

I have a rooted Redmi 4X(santoni) in which I have flashed TWRP 3.5.x I had flashed Havoc OS vanilla as the OS in it with OpenGapps ver 10.
Up until today morning it worked perfectly fine, I noticed the battery was at 3% so I plugged it in. When I tried to turn it on later, it got past the "Mi Unlocked" screen, Havoc OS startup animation was working but then the phone abruptly shut down.
However I was able to boot into fastboot with Power + volume down. I was also able to boot into recovery with Power + Both volume buttons.

First I though it was a battery issue, but the battery percentage shown in the screen when the phone is shut down showed 86%. When I boot into TWRP it also shows 86%, after some time it dropped to 85%, so nothing unusual there. I generally get 1+ days of backup.

Next I thought it was an issue with Havoc OS so I booted into TWRP, wiped the device (I selected every partition manually to wipe them) and then I formatted the phone. Then I powered off the phone and booted into recovery.
I then transferred the zip files of latest crDroid 6.x vanilla, OpenGapps ver 10 and the latest apk of Magisk to install later. I selected install from TWRP's menu and clicked on crDroid's ZIP, it completed successfully without errors (as far as I could tell). I tried to boot into crDroid, but the phone again shut down after showing boot animation for sometime.

Then I booted into recovery and connected my santoni device to my Arch Linux laptop. I opened up my terminal and ran "adb shell" which opened up a root prompt. Then I ran "dmesg > log". I then exited out of there and ran "adb pull log" on my laptop.

This is the output of dmesg.

I looked at this answer which led me down a huge rabbit hole none of which I understood. Upon running "adb shell" and "logcat" in it, I get

/sbin/sh: logcat: not found

with error code 127 in terminal ( which I get in Linux if command not found). I also get this same error when I run only adb logcat from my terminal as non-root user while booted into TWRP.
I can't figure out how to boot into my system. I can't figure out how to give better logs either. For now I will shut down my phone, any assistance appreciated.
Despite following the link given in the comments, my issue still persists exactly as it did before. Hence the link wasn't of much help in this case.
PS: I would appreciate it if you could also give me feedback on the quality of my question and how I may improve it.

did you disable dm-verity? dmesg from recovery isn't of any use. logcat is adb command/argument and works only when usb-debugging is enabled (local.prop)

Like every option that appears when you boot into TWRP and select Wipe and Advnaced WIpe - dalvik/art cache, system,data,internal storage,cache. Further, what is dm-verity and how do I disable it?

Does this answer your question? Install Magisk in TWRP, with "Keep DM-Verity/AVB 2.0" option?

Formatting data has worked every time. In fact the first time I'd tried to boot without formatting data the system wouldn't boot but after formatting it worked fine. Also how would I go about creating the file where you say I should? I can't access the / partition when connected via MTP. Further, How will I install Magisk if I can't even boot into my OS far less install the app and patch the file?

So I made a file in internal storage of phone called .magisk and appended those two line. Renamed magisk.apk to magisk.zip and installed with TWRP no errors. Then booted into crDroid and setup worked fine. Suddenly phone shut down. Boot back into TWRP, battery is 77%, it was 77% in crDroid too.This behaviour continues even if I start up phone while plugged in

I did everything you said @alecxs but problem still persists

Let us continue this discussion in chat.


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Restore mmssms.db without root?
So I have managed to get this file from a broken install, I'd like to restore my sms but I don't want to root my phone. How can I manage this ?
I've thought about converting to xml and using sms backup and restore but this will be tedious because of the format converting.
What else do you suggest ?

copy it to another device which is rooted and export xml

"another rooted device" can also be a rooted emulator...

I didn't work of course, I posted my solution

So I decided to export the SQL data as CSV and then imported in Excel.
I then checked the XML format from SMS backup and Restore, made it match, exported it as XML from Excel.
And finally you can just restore it.

good. please make this answer useful for others. How did you export csv? which tables/columns did you use, and how did you sort to made it match? how did you export xml?


text:
Share internet through otg-ethernet from terminal
I know other threads already exist but none of them answer this specifically.
My OTG ethernet cable works only when used as a client, i.e. when a DHCP server is recognized.
I want to be able to share my 4G connexion to a router trough the WAN port. Android doesn't support this natively, so I'm guessing I'll have to create my own AP but I'm not sure exactly how do that trough the terminal.
I'm guessing there is some NAT involved.

I already commented on your previous question: Use an external WIFI dongle as a hotspot

This is different I never asked about a wifi dongle

There's no difference in network configuration of a WiFi dongle or Ethernet adapter. Both are connected through USB, both appear as a network interface.

I'm trying to use rmneet_data1 as AP but the mask is /30 should I adjust accordingly ?

Don't know what you are trying to do. rmnet_data1 naming convention is used for Mobile Data network interfaces on devices with Qualcomm modems. You cannot use Mobile Data (but WiFi) interface as AP. Then NAT the traffic between both interfaces for internet sharing. Or you may even avoid NATing, but it's complicated setup: https://android.stackexchange.com/a/218562/218526

Sorry I meant as upstream, ethernet is the AP


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Shell script to stop multiple Android apps
My goal is to force stop multiple apps on the startup. The script can be executed with Magisk on boot by placing it in data/adb/post-fs-data.
I already tried writing
am force-stop com.exp1

and also with
#!/system/bin/sh

but it didn't work
What should I write on it?

See How to run an executable on boot and Disable autostart on boot and restrict background execution.


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Is it safe to turn off kernel panic in Android?
So I'm using a custom kernel that overclocked my CPU and GPU. I turned down the frequency to stock but the big cpu freq can't be set(restore itself to default after some time), causing my phone to heat up if I'm having heavy workload/game. When my phone is really hot, kernel panic comes in and reboot my phone, I hate it when it happen while I'm gaming.
I looked up why it reboot and the cause is kernel panic. So I searched how to disable kernel panic and so I did.
My phone doesn't reboot anymore. But I'm thinking is it okay to disable it? I can't use another kernel cause it the only one kernel that support custom rom and having hotplug (really helpful at saving battery and less cpu heat). And I don't know how to recompile a kernel.
My tweaks.sh
sysctl -w kernel.panic=0
sysctl -w kernel.panic_on_oops=0
sysctl -w kernel.softlockup_panic=0

Forcing operating system to continue execution when it thinks it should abort is never safe. In extreme cases this may damage the hardware, as you pointed out that panic occurs due to overheating. Better avoid. Even better is to never let the temperature raise above safe threshold. Kernel documentation: https://www.kernel.org/doc/Documentation/sysctl/kernel.txt


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How to restore whatsapp data from local storage?
I have tried multiple options to restore data from internal storage. Unfortunately, none of them has been successful. Every time I get prompted to google drive back up even though I don't have any backup on google drive and I have disconnected WhatsApp from my google drive accounts. Can anyone help please?

Have you tried the step mentioned on WhatsApp Help Center?

yes its not helpful

There are similar questions asked already, and the most recent answer is to disable WhatsApp backup from Google Drive first: 1, 2. There's also the older approach mentioned on 3. Please try and let us know if any of it works. Thanks.


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How to get 3rd and 4th IMEI number for an android using ADB command?
I am using service call iphonesubinfo 3 i32 1 to get the 2nd IMEI number. I want to get 3rd and 4th number for quad sim phone. How to get that using adb shell command?

The way you get 1st and 2nd IMEIs: https://android.stackexchange.com/a/219105/218526


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Android devices getting slower over time
At work we have a bunch of Casio handheld android terminals (DT-X400). They do not have any connectivity to the internet (so no updates), almost all apps are disabled except for those we use for work. We used them for about a year, and recently got a few more.
When we started using the new ones, we discovered that they perform a way, way better:

no lag;
navigating within applications is fast and smooth;

while the others feels sluggish:

it takes few minutes to boot up;
often it lags while doing simple actions, like scrolling on small lists;
opening apps takes a long time (> 30 seconds for calculator) - when you click on the app icon it looks like it freezes, then after a while screen goes black and after few more seconds app opens up.

The new ones performs a lot better when doing same tasks.
They are all the same model, hardware is the same, drivers versions on every device are also the same. All of these terminals runs Android 8.1.
I tried clearing memory, disabling all the apps I can, later did a factory reset, but performance did not improved.
So my questions are:

What can cause such slowdowns of android devices?
Is there any way to improve performance, without getting root access?

Update:
As of the suggestions in the question comments, I have tried swapping bateries from the new devices to the old ones and also powering them completely off. Neither option showed any performance improvements.
I am also aware about aging flash memory, after the weekend I will try to run some test on both devices to compare memory performance and update my question with the results and methods used.

Do you keep the devices always on or do you shutdown them when not in use? How good is the battery of the old devices compared to the new devices? When it comes to performance slowdown because of hardware only flash memory (flash memory can get slower it it is written to very often) and defect cooling system because of physical defects (e.g. by bending the device) come into my mind.

@Robert Devices are always on, for few of them we have bought new batteries two months earlier, and they hold the charges pretty good. Still, as they are easily changeable I will try putting the new ones into the old devices just in case it is causing problems.
As for the memory - it may be, the one app we use has a SQLite database that is often written. Also, the app creates about 20 .txt files every day with an average size of 20KB. Maybe there is way to check it?
As for the physical defects, the devices only have some scratches but there is no visible physical damages.

Then may be you should try to shut down them for a few minutes. I recently had to learn that it sometime makes a big difference between rebooting a device and shutdown and later turn it on again (internally some chips get a "hard reboot" as they are not powered anymore). Not sure if it makes a difference but worth a try.

Thanks for the advice, I will try shutting them down completely. Later I will post the results.

After powering two of the devices off for 10 minutes, and taking batteries out nothing have changed.

Does this answer your question? Why a phone gets slower as time passes?

@beeshyams Thanks for the link, it explains about TRIM support (which in my case is supported) and about aging flash memory (which I believe is causing my problem). But I still hope somebody can suggest other possible causes or tips for improving devices performance.


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Downloaded a phising application, what steps should I take next?
My dad accidentally downloaded a fishy DHL tracking application. The application was downloaded through a SMS he received.
I immediately noticed that the application wasn't accessible through the apps list. Whenever I click on it, the apps list immediately closes. The application had access rights to his contacts, phone and SMS. Trying to deny to rights was not possible as the application immediately turned those rights back on.
My first intuition was that "Hey, an installed application shouldn't have system level access to system applications" as such, I figured that if kept trying to click the delete button faster than that the application closes the apps list, I should be safe...
And guess what, it worked! I was able to delete the application that way... lame.
But now that the immediate threat is gone, should I worry about any lingering landmines?
Is there a way to be sure its all safe? Should I check anything specific? I made sure my dad changed his passwords.
Thanks in advance!


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Bootloader won't load any commands
My Bootloader won't do anything, when I type fastboot getvar all it stops giving the strings half way, or when typing any other command it will only give ... and nothing more. Bootloader log only shows: cmd: oem-info and nothing more

check cable+jack (loose or broken)

I already tried different ports and pcs. Cable is fine too. It is detected in computer in both fastboot and adb state. Is there any way to check for bootloader logs in a more advanced way?( Too see if it shows any errors) The default only shows me my commands

must be the cable or port related. maybe COM transfer rate (SuperSpeed) is too high. Do you use latest version? https://www.xda-developers.com/google-releases-separate-adb-and-fastboot-binary-downloads

Yes I do use latest version, thanks. Idk what this COM transfer rate is...

connect intermediate usb 2.0 hub to eliminate speed problems

Hi, looks like you've found the solution with the help of someone, which is great! Instead of posting an answer that looks like a comment (it's technically "not an answer" and will get deleted), consider writing a proper answer since self-answering is not only allowed, but even encouraged! Otherwise, you might want to ask them to post a proper answer for you instead. Thanks!


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How to understand the confusing naming conventions of modern Android companies and prevent getting ripped off?
Here's the reason for this post and my annoyance -
There is a phone called Redmi 9 whose codename is Lancelot and there is a decent amount of community support for it, TWRP is available as well as some ROMS.
Seeing this I was impressed and ordered it off of Amazon. It clearly said Redmi 9 and the same model with the same price is available on Redmi's official site as well.
However when I got the phone, enabled USB debugging connected it to my pc and ran adb shell, the name I got in the prompt was cattail and not lancelot!!!
And cattail has next to no community support for rooting and stuff, no TWRP either.
Googling cattail vs lancelot gives a bunch of results and there is a difference in camera alignment in the two phones.
Further while Lancelot is a decent enough phone in itself, cattail is absolutely disappointing. Searching for lancelot on amazon or redmi shows up nothing and when I search "Redmi 9 code name" in any search engine, I got lancelot!! I bought the Redmi 9 believing it was something it was not.
Is Redmi and Amazon straight up lying or am I missing something here? Where is the guide to understanding naming conventions of smartphones? How do I and everyone else who uses Android prevent companies from ripping me/us off?

Phone manufacturer like Samsung and Xiaomi sometimes create devices that have the same name but are dedicated for a certain area like your cattail for India or Samsung's sepcial devices for the US market. Therefore I would always recommend to check a device database like GSMArena where the list available variants or link to very similar phones. Comparing both phones allows you to see that they have a different display resolution and chipset (the G35 chipset of the Indian version is even mentioned in the linked Amazon product page).

Hindsight is 20/20, there's an article that explains all Redmi 9 variants on Xiaomist. The Redmi India's official site and the Amazon India's link show the exact model of Redmi 9 (India) though.

I assume stuff for lancelot will not work with cattail? I basically got ripped off and I don't like this practice in the least.

Yes, it won't work. While I sympathize with you caveat emptor

btw the model name of your phone indicates Poco C3 so i won't give that much on it. cattail is right


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How to restore a Nandroid backup without TWRP?
I have bricked my OnePlus 5 device (black screen, blue LED, bootloader locked, no TWRP on my device). I have tried almost everything (sideloading the official OnePlus firmware through adb, using the MSM Download tool to flash the .ops file - The flash is successful but I get the black screen, blue LED at boot again), none of it seems to work. But, I'm not prepared to give up.
So, I was thinking maybe if I get my hands on another OnePlus 5 device  and take a Nandroid backup of the device using TWRP with the OEM unlock option enabled in Developer Settings and use this backup to flash my original bricked OnePlus 5. The point of taking a backup with the OEM unlock option enabled in developer settings is to somehow load this Nandroid backup on my bricked OnePlus 5 device (so that I at least can unlock my bootloader and explore other options of restoring my device by flashing a custom recovery).
Now, the question is - If I manage to take a Nandroid backup of another working OnePlus 5 device, what are my options of loading this Nandroid backup on my bricked device (as I don't have TWRP on the bricked device).
Any guidance on this will be greatly appreciated.
Thanks.

you can't BECAUSE of locked bootloader


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How can I see request and network profiling on an app that is decompiled by Android studio?
I chose "Profile or Debug APK" in Android Studio and chose a downloaded apk. Then, when I try to profile it, I see spikes in network tab, but I cannot see network requests and responses.

Any solution for this?
Does downloading apk from websites matters?

I believe it's only possible on debuggable apps. APKs from the internet are usually taken from the Play Store, and those have their debuggable flag set to false. Otherwise, they get prevented from being published.

@AndrewT. - Thanks for answering. So, if apps can't be released unless debuggable = false, then when Android studio has an option "debug pre-built apks" while opening android studio is counter statement. Which means, we can profile only the apps that we develop. Is that correct?

@sofs1 That is the purpose of Android Studio. But you can use apktool to decompile the app, change debuggable flag and recompile and sign it. Some apps my check for debuggable flag and signature and refuse to run but a lot will just run.


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How does root work in android phones? Does the concept of 'root' exists in android?
So I had an argument with someone over telegram if root exists or not in android.
My point of view is that like any linux kernels the concept of root exists but it's not accessible to other processes. That's where magisk comes in play, hacks the kernel permitting other apps to use the root functionality.
Now the other person mentions that the concept of root doesn't exist in android and mods like magisk implements it.
Now, which one is which? Does root exists in android phones or mods like magisk implement it?

Not clear what you mean by "exists". But everything you may want to know about root on Android devices is covered in my answer to: How Magisk works?.

For even more details see How to manually root a phone? and Is there a way to root an Android phone without unlocking the bootloader? and How does SuperSu provide root privilege? and What special privileges “/system/xbin/su” does have w.r.t. root access?.

the concept of user root doesn't "exist" on android. in linux world user profile is login user. but android "misuses" user profiles for it's application security concept. each app is another "user" to ensure apps running in "isolated" container and can't harm other apps. on top of this android uses namespace separation and selinux. magisk can deal with all of this and finally provides something what looks like user root, but the magic behind is different from linux (there exist multi user concept on android too but that is quite more confusing in scope of question, parallel apps, work profile)


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Can I edit an Apk for removing Ads even getting updates?
There are various sources for downloading an apk.
After installing an apk, Play Store detects the app. And it shows updates, if any update is available.
After updating the app, the app starts ads.
Can I edit the apk such a way so that even after updating the app from Play Store, it shouldn’t start ads?
If yes, please let me know and elaborate steps.
I’ll be thankful for giving your time.
With Regards
FewL

Editing an APK destroys the signature and you have resign using a different key. Afterwards you can't install updates from Play Store.

Alternatives are using an Ad-Blocker – or get your apps from F-Droid whenever possible. Both approaches can be combined, of course.


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Adoptable storage filesystem?
I have a sdcard split into two partition: portable and adoptable.
Not long time ago my /data is formatted as F2FS, really unstable on my device. So I recently format it again to EXT4. I'm noticing that my adoptable storage is still F2FS even though I already format it again using
sm partition disk:***,** mixed 69

Is the adoptable filesystem following the device /data filesystem or it's default to something?


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Move the pointer with the head on android
Allow me to introduce myself, my name is Stéphane, I am quadriplegic.
I am running this topic because I need help.
My disability means that I cannot use my arms. I'm looking for a system where I can move the mouse cursor with my head on an android tablet.
I found a system with OpenCv but it's on Windows Would it be possible to do the same on android ?

This app claims to do this. It has a good rating too. You may like to test it

I tried but it is not very reliable


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Minimum requirements for TWRP
I am trying to figure out why some devices like mine (Pixel 4a, Android 11 ) don't have a TWRP. It seems to be a fairly popular device, so I am presuming lack of developer support isn't a reason.
Some pointers I could find :

Lack of space on the RAM disk? Thread TWRP on the P4a?

Thanks to alecxs who pointed out Test build for Android 10, which again speculates on reasons (surprisingly, no one confirmed it fully works on Android 10).

Kernel support needed? This kernel claims to support TWRP

So, I am just trying to understand from a user point of view what the limitations are ( I do miss nandroid backup, at times).
Reasons, anyone?

For the first point, please let me know the command to generate information if needed

minimum requirement for official TWRP is 1) some developer 2) who owns that device 3) is interested in becoming maintainer. you still can go with unofficial TWRP meanwhile https://www.getdroidtips.com/twrp-recovery-google-pixel-4a

@alecxs thanks, I am assuming 1 and 2, as I mentioned in first paragraph. I saw 3, doesn't work and couldn't find more as to why//besides, it would be nice to just boot into it to take backup and that too doesn't work//Most importantly, developer unknown, so I am kind of scared to push on this

@alecxs also point 2, barring this linked kernel, other custom kernels don't talk of it, leading me to think kernel support is also mandatory

flash sunfish_twrp201017-test5.img along with vbmeta_disabled.img

Can you please link vbmeta_disabled.img and the exact process please @alecxs

Does this answer your question? Android Verified Boot and generation of vbmeta image

@alecxs thanks, will look into it but the main question remains - what are the limitations if any?

https://forum.xda-developers.com/showthread.php?t=4179101

i am not quite sure but there might some conflict with magisk as recovery_ramdisk lives in boot.img. afair order is first install twrp then magisk

Thanks @alecxs, don't know how I missed that but it won't work on Android 11 (I am on it)

I don't see a reason why it shouldn't work except fastboot boot is disabled on 11 (or vbmeta)


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Device not shown on ADB even after pairing for wireless debugging on Linux
Wireless debugging seems to pair, but then the device just does not show up. I tried it on Mac and it works, but it does not work on Linux. I am on a Samsung phone.
I run adb pair [IP]:[PORT] [CODE]. It executes successfully and tells me that I am paired with the device. Then I run adb devices and it is just blank.
On my phone, it doesn't say that it is paired to myuser@hostname, but rather root@hostname for some reason. I even tried logging in as root and listing the devices but it is of no avail.
The above steps work fine and list the device on a Mac. The phone also shows "Connected" next to the hostname and user, and the user is not root but rather the username.
I have tried-:

Disabling firewall
Trying the tools from the official repository, AUR package, google website, etc.
Restarting my PC and Android phone

Yes you still need to do adb connect after pairing. Pairing replaces the old RSA key authentication, but making connection with the paired device is still up to the user. Though making it  a part of pairing isn't a bad idea.

This works on macOS, so this not working on Linux seems like a bug.

As per the official documentation (snapshot of 22 January 2022), after pairing the device, the user still needs to manually connect the device

(For Linux or Microsoft Windows only) Run adb connect ipaddr:port. Use the IP address and port under Wireless debugging.

Despite it is not mentioned on the current documentation anymore, this step is still necessary (tested on Windows).

Relevant ADB issue tracker report: https://issuetracker.google.com/issues/225320059

This worked for me. Just had to connect after completing the pair.

I could make it work only by not specifying the port (adb connect ipaddr). Otherwise a Connection refused error is returned.

I had to use the same ipaddr:port from the debugging screen, not the same as I used adb pair that is the popup when you go "pair with a code" on Android


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How to resolve an encryption issue?
I used a lockscreen to encrypt my phone and accidentally messed up the system and TWRP. I've since formatted it and am using it normally, albeit without root this time lol. But, just in case, I made a backup of the data beforehand. Is it possible to decrypt it if I remember the lockscreen? I can't get encryption keys from the phone because I've already formatted it to a new system, but can I get them from another software that can read the files? I read about it online, and apparently there are a bunch of strange commands you need to type into the system, and I'm not too familiar with this because I don't want to mess anything up, and it's really quite complicated stuff to understand. What I gathered from this was that you would have to format the phone again in order to recover the filesystem data, which I obviously cannot do. So please don't just recommend esoteric guides to me as if I'll magically understand everything; that's why I'm asking in the first place. So, is there a solution here that a layperson can understand? Can I somehow decrypt the image using only a PC, inputting the password through some special tool or something? Or is there some other way?

no way. once encryption key is gone no software in the world can read the files. that's the purpose of encryption. independent using password or not, the key is lost forever

@alecxs But I know the password in any case, so it is possible to maybe recover from the image?

the password is worthless without the encryption key (which is random generated)

@alecxs Is there something I can do if I backed up the whole storage beforehand? Is the encryption key stored there?

@alecxs Well it was on Android 10, a full backup of mmcblk0p66, can this be recovered some way?

depends on encryption type. for FDE it is possible only if crypto footer is present at end of mmcblk0p66. for FBE it is possible only if TEE keystore is not flushed (should not happen on formatting)

@alecxs I believe it's FDE, actually. What can I do, then?

adb push mmcblk0p66 /dev/block/mmcblk0p66 and reboot

@alecxs Is it just going to work like that? Like, no extra step?

there is no extra step. either crypto footer is last 16384 bytes of mmcblk0p66 then it will restored and TWRP is able to decrypt. or crypto footer is located other partition (which you don't have backup) and therefore unable to decrypt


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Fail to find an Android device sound file
In the clock app (bedtime tab, sleep sounds) I can choose a device sound Deep space.
I would love to use it as my alarm sound.
Every file-exploring app that I have used hasn't found this file.
How can I?

I would suggest extracting the APK of the app from /data/app. Copy it to sdcard.
Rename clock.apk to clock.zip, extract it and starts looking for sound files.
Format will probably be something like deep_space.ogg.
Good luck

any less intrusive way to rip it?

It's pretty simple really, only other thing I can think of is recording it.

Sorry for asking, but I cannot find  /data/data using a few file managers (including Google "files").

So you need to find the package name of the app you want and then search for thee package name in /data/app/, the APK will be there. I'd recommend using FX file explorer, you can get the APK  directly there is an option in the app to do that.


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Samsung A21S support USB-C to HDMI?
I buyed a USB-C to HDMI device and it didnt work, so i thought the problem is the device and tryed to get a refund.
I have no other device capable of testing it and i searched in the entire Internet about it but found nothing.
I found something about HML and my device does not support it, but some people said that the HDMI works even without the device supporting HML.

Samsung flagship devices support it - not all. Check the lists at mhltech.org and everybodywiki.com. I cannot find the A21s or its model alias SM-A217F there.


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What does it mean for a bootloader to be locked/unlocked?
What exactly does it mean in this context to be locked anyways?

Also see the tag wiki to help understand better//  This answer too covers it while addressing a different problem

Related: What are the various ways an Android phone can be locked?

Does this answer your question? What are the various ways an Android phone can be locked?

bit oversimplyfied three main partitions are aboot (little kernel) + boot (kernel) + system (rom) but truth is more complicated. custom rom comes with boot + system only. aboot itself is never replaced. it's worth mention even bootloader is splitted in primary + secondary bootloader and lives in protected area, whereas aboot (layman's term "bootloader") is actually the third link in boot chain. unlocked bootloader affects only the fourt stage (allows untrusted kernel + rom). chain of trust continues with verified boot

https://edk2-docs.gitbook.io/understanding-the-uefi-secure-boot-chain/additional_secure_boot_chain_implementations/android_verified_boot

The definitive answer comes from the android documentation itself

By default, most Android devices ship with a locked bootloader, meaning that users can't flash the bootloader or device partitions. https://source.android.com/devices/bootloader/locking_unlocking

So functionally it's a prevention mechanism for altering these protected filesystem partitions on the device.
Some fundamental background is worth mentioning regarding these special partitions.

Any Android phone has three main partitions: boot loader, Android ROM, and recovery. The boot loader is present in the first partition and is the first program that runs when the phone is powered on.
The primary role of the Boot Loader is to take care of low-level hardware initialization and boot the device into other partitions. It usually loads the Android partition, commonly called as Android ROM. Android ROM contains all the operating system files that are necessary to run the device. The recovery partition, commonly called as stock recovery, is used to delete all user data and files or to perform system updates.
https://resources.infosecinstitute.com/topic/practical-android-phone-forensics/

A bootloader lock prevents ROM/firmware from unwanted modifications. It is one link in the secure boot chain of trust.
It therefore plays important role in data security protecting your personal data against theft (it won't however protect your data from deleting, factory reset is always possible). More can be read about the subject here
Is Android's system recovery a firmware thing or Android thing? Can factory reset be prevented?
Additional information can be found in this related question that asked to disambiguate a locked device from a locked bootloader device.
unlocked device vs. unlocked bootloader. The key takeaways are

boot loader loads the core Android OS code.
locked bootloaders use digital signatures to verify the Android code it's loading.
an unlocked bootloader will load any ROM.

This other answer though not really offering a precise definition gives some insight into the motivations behind the design of the boot loader being locked
what is a bootloader unlocked phone?
A prerequisite for a device to be locked is that it must first be flashed with a ROM image that had the lock support option baked into it at build time with the build property ro.oem_unlock_supported set to 1 as in a build.prop file. Only then can a device have the ability to toggle between a locked and unlocked state, otherwise it will always be unlocked by default.

(if you think about on which stage in boot chain build.prop is located) the build property refers to the oem unlock toggle in developer options only, not actually to the bootloader lock itself. therefore your last sentence is wrong. devices can shipped locked state without having that property. also bootloader can be non-unlockable even with get_unlock_ability=1 and/or OEM unlocking enabled: https://android.stackexchange.com/q/233310 https://android.stackexchange.com/q/234025

That's good, that last paragraph I synthesized with some uncertainty just because I haven't done any android development. I tried to find documentation of where in an android project you integrate and refer the build to one of these files, it seemed like there was a way but I was filling in the blank in my mind analogizing with visual studio property sheets https://docs.microsoft.com/en-us/cpp/build/create-reusable-property-configurations?view=msvc-160


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If a phone is encrypted (Android 5.1) but user doesn't use a screen lock, and then does factory reset, is data secure?
If I have a phone running Android 5.1 and it is encrypted, but I don't use a lock/PIN for unlocking and using the phone, does that mean if if I do a factory reset, the data on the phone can still be recovered? I mean, does not using a screen lock mess up this process of encryption+factory reset to wipe data?

If user password/PIN/pattern is not set, data is encrypted with the default_password provided that encryption is enabled. And encrypted data is highly unlikely to be recoverable after factory reset. See my answers to Data deleted after encryption - recoverable? and Can user data be recovered after formatting and flashing stock ROM?.

@IrfanLatif Thank you. If the data was not encrypted, then there's a good chance it can be recovered even after fctry reset, isn't there?

Yes............


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Access Spotify cached files
How to use cached files in Spotify application under Android ?
The mentioned file extensions are ".file" , which are not normally playable, but it is clear from the size and type of archiving that they can be used offline by the application.  The threshold storage address
is as follows:
/internal storage/android/data/com.spotofy.music/files/spotifycash/storage

There's always a possibility for streaming platforms to encrypt the cache/offline files (i.e. DRM) so that only their app can play it exclusively.

Thank you .  Is there a way other than the normal mode in the software to download music in this space ?

@Merlin: Sorry but I don't understand your last comment. What do you actually want to achieve?

Ok, I just want to be able to download music files from Spotify.

Spotify has an offline mode if you have a paid account. That is what they provide, of you want to use the downloaded files outside of Spotify Andrew already gave you the answer that those files are DRM encrypted and thus can't be used outside of Spotify.

got this app from 4pda. guess with that source code someone can decode files

microsoft has blocked source code, one more reason to not use github. you can still find the binary patch on gitlab and ask the author for wiki

@Merlin the problem is, when you use (or even subscribe to) Spotify, Spotify only gives you access to play audio files within their platform, but you don't own the audio files in the first place, so it's potentially illegal to download them for other uses outside of Spotify. There are of course other ways to achieve what you want, but I can't mention them due to personal reason.

@alecxs I don't think a more than 3 years old Spotify app will still work. Spotify releases new apps very frequently and the chance that one of those apps includes a protocol change is very high. I assume this is also done to make reverse engineering ineffective.

the app works fine no ads, i use it on android 7

Well, those files might be stored in /root/data/data/spotify but wont be playable or even accessible without superuser privileges

yes . Yes I have access to the file cache in the storage location but unfortunately the files are apparently encrypted with the ".file" extension


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Can't reinstall apps from SD card after reboot
This is the first time my phone randomly rebooted, I didn't think much of it until all my apps disappeared. The apps in the internal storage is still there but the apps that was moved to the SD were all gone. I went to the play store to try to get them back but it won't install.
Please help
LG - SP320

clone the (broken?) sdcard to another one and try to reboot until your sdcard is detected again (loose tray?)


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Removed battery while phone plugged in
I accidentally removed the battery from LG G3 while plugged in and charging, does this damage the battery or the phone?

When you removed the battery did the phone stay on or did it instantly went off? As long as device did not went off but stayed on I don't see a problem.

It turned off and show a battery with exclamation mark inside

Removing power from a running phone may damage a lot especially if there were write operations active on flash memory at that moment.

that won't damage anything because it's not unusual for smartphones that battery runs out of power. journaling file system can handle such emmc writing failures very well. powering smartphone without battery is a different story. most ac chargers won't deliver stable dc current that's why power is only used for charging, while phone is powered by battery only. therefore it should make no difference if charger was connected at the time of battery removal or not


text:
USB C hub and charging at the same time
I bought a USB C hub with charging integrated but as soon as I plug in the charging cable to the hub the other ports stop working and the phone only charges. The USB ports and Ethernet ports stop working while the hub gets external power.
Does anybody have a solution or know about a hub that works both for charging and OTG on Android 11 ?

Does this answer your question? Can OTG HUB charge with connected charger more than 0.5A?

Does this answer your question? simultaneous USB-OTG and charging

Those threads are pretty old and don't tackle exactly the same problem. My device does charge and more than 0.5A when plugged and the second guy built a custom device. I'm using a newer phone/os and not a custom cable. I'm looking for someone with recent experience with the subject.

Using an USB-c port for charging (power input) and data (port used as USB master) at the same time is possible but as far as I know it has not been implemented for smartphones. On PC notebooks this is nothing unusual but on a smartphone it seems to be complicated. Not sure if this is a technical limitation or just nobody ever implemented it.

I edited the question to make it clearer. Furthermore, I've heard of people doing it, it should be possible with some kernel tweaking and/or root.

i am using otg charge hub to power usb-c ethernet in order to save battery, but no phone or tablet is charged. i have compiled kernel and can edit source code, i am very interested in solution too

It seams that my issue was One Plus's Oxygen OS didn't support this feature. I installed a few kernels hoping that one would fix it and it did. The kernel is called Dora based on nem0.

I edited would you mind sharing where I can find the stuff necessary to ad this functionality.

that one? will have a look next days thx
https://github.com/nem0-z/dora_kernel_oneplus_sm8150

yes this is the one

I've seen looking for days! What OnePlus did you use and which OS did you install with this kernel? Any ideas if this particular one should work on a OnePlus 3T?

I was beginning to think that this maybe was a hardware limitation or the OP3 since I've tried 5 different USB OTG cables/splitters


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How to get Android Phone storage as a drive path in Windows PC
I am using MI Note 5 Pro android version 9.0 and Windows 10 Basic.
On USB plugging('File Transfer' selected), I can only access files from Phone by normal copy paste(ctrl-c/v) but cannot access full file path from Phone because there is no drive letter assigned.

where disk is sd card.
I am getting files path as "This PC\Redmi Note 5 Pro\Internal shared storage" but want something like "P:\Redmi Note 5 Pro\Internal shared storage" How to get it without rooting phone?
Purpose: I want to backup my phone data to PC periodically using "Areca backup" open source utility which creates incremental backup. Note: I will not be writing any data to Phone but will only need to read it for copy operation.

Does this answer your question? Setting up an Android device as file server

Software like MTPdrive directly mounts a device with a drive letter.

I have MPTDrive and it is very difficult to get a stable connection. And if you do manage to get the phone to be recognized by the app (even though Windows sees it fine), when I try to use it to back up my phone SD card, it drops the connection mid-way through the backup and I'm back to not being able to connect the phone to the app.

Hi Ezriderz, I am not using any app on windows PC. Procedure is like- connect phone using usb wire, a popup will appear in Android phone to file transfer, do nothing, etc. Select file transfer. Then you will be able to open internal storage or sd card drive from my computer just like default c/d drive you have. Then I use freefilesync app with keeping phone paths as mtp: prefix. The one mentioned in answer do create some problems with ftp incompatible files so i am no longer using that solution.

MTP the protocol used for accessing the phone is not implemented as file-system on plain Windows thus you don't get a drive letter without third party software. Additionally MTP is a pretty unstable, ineffective and slow file-system which makes it not a good choice for backup.
But be aware that the files you can access via MTP are just the tip of the ice berg, making a backup of those data will not allow you to restore your phone (except for some apps that explicitly place their files on shared storage section).
If you still want to backup the data you should enable Android Debug Bridge (adb) and use adb-sync go copy the data to your PC. From there you can then make a backup.

Hi, Thanks for answering. I actually need a way to keep copy of files to my PC like documents, images, etc lying in phone here and there and don't care about full backup having app settings too. So basically an easier way to copy paste phone's filemanager contents.

@PalashBansal Then adb-sync would be perfect for you. Also having ADB enabled is always a good preparation in case the phone display breaks. In such a case ADB allows to backup the files even if the display is broken. MTP however needs an unlocked device which requires a working display.

AndroidDrive does this.
If you're looking to transfer files from the phone, its very buggy in that regard though.

Why recommend it if its buggy?

Because, perhaps someone can fix it. The source code is available.


text:
Display glitches in certain apps
Device specs

I have so far only noticed this problem in Quora app, and Chrome (some pages). But these are the apps I almost always browse the net with. I did not notice any such issue offline.  It has been around three days.

These are just a few examples of the types of glitches that occur.
I have tried:
-uninstalling Google's WebView after hearing of a recent update causing trouble
-forcing GPU rendering.
-Reinstalling Chrome and Quora.
Just in case this helps: I had observed text glitches on Chrome for quite some time before this started. Usually, one or a few words would be disfigured. Changing zoom would correct it. Also, today many files of mine have disappeared. They aren't hidden, just nowhere to be seen.
Oh yeah and

Do you encounter the same problems with the pre-installed manufacturer browser?

@MorrisonChang apparently not.

I would also check in Firefox as they use a different render engine. If rebooting the phone doesn't clear the problem up in Chrome, it could be Chrome graphics driver issue or hardware fault. You may want to file a bug report: https://support.google.com/chrome/answer/95315?co=GENIE.Platform%3DAndroid&oco=1

@MorrisonChang I forgot to mention that I rebooted

The only thing that worked for me was disabling "GPU rasterization" in chrome://flags


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Redmi 8 bootloop
My Redmi 8 phone is in bootloop. It got stuck with its Remi logo and does not start.
I am trying to unlock the bootloader but I didn't find a way other than mi unlock which I don't know how to use it without knowing my mi account credentials.
Please help me...
Thanks in advance...

What were you doing before the phone got stuck in a bootloop? Did you do a system update/upgrade? Did the device reboot itself on its own or did you do reboot for some reason and observed bootloop? Do make an [edit] to answer all those questions. That said, if your device gets stuck in a bootloop, you shouldn't be going after bootloader unlocking. Factory reset the device. If that doesn't work, only then try to unlock the bootloader (would be harder for you in this situation). Do note that unlocking bootloader automatically factory resets the device!

i don't recommend factory reset without knowing mi account, unless you find method to by-pass FRP

this guide give you a base to start reading about EDL mode. i have heared about even EDL mode is asking for mi account authorization on new devices, but worth a try. once you
have access in EDL mode you can flash firmware and erase FRP partition https://android.stackexchange.com/q/226838

search for patched firehose programmer or ask on xda forum

just a broad collection (unfiltered) good luck romprovider.com, firmware27.com, leakite.com, github.com, tuserhp.com, firmwarego.com

https://xiaomifirmwareupdater.com/archive/miui/olive


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Use USB OTG mic audio device for audio input ONLY (use mic with headphones)
I want to record some audio using a USB mic and my OTG-supporting Android phone. The problem is, because the phone recognizes the mic as an audio input/output device even though the mic has no physical way to make sound, I can’t use the headphone jack while the mic is plugged in. Is there an app or a setting I can use to only use the input portion of the USB audio device, and instead use the 3.5mm headphone jack for output?

Can you please exactly name the USB microphone you use? May be the mic uses an audio chip that supports input and output (but does no make use of the output) which is then detected by Android.

It’s a Fifine K669.


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Can the Samsung Android phone be made to not lock the screen after 3 minutes?
I am using Android 11 and Samsung's OneUI 3.1 (updated as of May 1, 2021), and it'd show the "Lock" icon right at the center of the screen and dim everything down after 3 minutes.
All the other OnePlus or Xiaomi phone do not do that.  If I follow the instruction online to go to Settings -> Lock Screen -> Lock Type to "None", it is still happening.  Is there a way to disable it totally?
P.S. There was a "Screen Timeout" in one of the settings option, but (1) It is set to 30 minutes but the phone still shows the lock icon after 3 minutes, and (2) I'd like to set it to "never" but there is no such option

Look for something like "display timeout" or "screen timeout" in settings, that's where you usually adjust that. No idea where exactly Samsung puts that, but the "search" feature in settings should help you finding it.

This should help I guess https://www.samsung.com/au/support/mobile-devices/adjust-screen-timeout/

yes, I saw the "timeout" before but setting it has no effect (please see the added P.S. in the question).

MacroDroid can do it

Seems like I only see this particular lock screen when playing a game.
When the lock screen appears, tap the padlock icon near the bottom of the screen.
You'll then see an interface that allows you to add or decrease time. Tap the + several times to increase the screen lock to the amount of time you prefer, or even to never.


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Is there a way to make an apkmirror.com app behave exactly the same as the app from Google Play Store and Galaxy Store?
There can be a subtle difference on how the app behave:

Xiaomi phones using Dual app for Pokemon Go
Galaxy phone using Pokemon Go from Google Play Store and Pokemon Go from Galaxy Store
OnePlus using Pokemon Go from Google Play Store and Pokemon Go from apkmirror.com (there is no other choice because it doesn't have a OnePlus Store)
Xiaomi phones using method (3) above just to experiment

I noticed if it is (3) and (4) above, then if we click on the Pokemon Go Store, the page is all blank.  If I show the app from apkmirror.com on the OnePlus App info -> Advanced in Settings, then it shows "None", as opposed to "Google Play Store".
Is there a way to make the app behave exactly the same as if it comes from the Google Play Store or Galaxy Store?

First there may be different app versions for each store. Where apkmirror.com gets it's versions is not defined, as users upload the APKs. Additionally Android records if an app has been installed from Google Play Store or not (using the "Play Store Install Referrer"). Based on this data an app can behave differently. Therefore it could be a different app and it could be the way how you have installed the app.

so theoretically, for Angry Birds Classic, when this app is removed from the Google Play Store, but archived on apkmirror.com, the app can really choose to think, "Not from Google Play Store and Not from Galaxy Store, therefore stop the app right there (not allowed to play)."

I just reread info about Play Store Install Referrer, it seems like this is Play Store only, therefore I don't know if Galaxy store also provides something like this. Using that referrer you could limit an app to direct Play Store installations. But I am not aware if any app really does something like this. Typically the installation referrer is mainly used for marketing.

... and for automatic updates via google play


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How do I compile and install USBguard on android?
Is it even possible to compile and install linux packages on android, if it is possible how do I install usbguard into android?

you can run static command line binaries from linux arm/aarch64 packages but no linux software, except you are running linux on top of android (linux deploy)

You should better ask such question on the USBguard mailing list. There they know better what requirements (kernel and other) have to be present for USBguard to run. As it requires a special service intergrating USBguard at least require root permissions on android plus various system modifications. Or directly develop a matching customROM with integrated USBguard.

As Robert said it won't simply work on Android since it relies on components like systemd, D-Bus based IPC and polkit, which are specific to Linux distros, not available on Android.


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Backup and restore file-based encryption keys
Android File-Based Encryption is implemented via fscrypt. How do you backup and restore fscrypt encryption keys? Both the master keys and the per-file keys would need to be backed up.

From your first link 1.Keymaster/Keystore and Gatekeeper must be implemented in a Trusted Execution Environment 2.Hardware Root of Trust and Verified Boot bound to the keymaster initialisation is required to ensure that Device Encryption credentials are not accessible by an unauthorized operating system // TEE is something that cannot be accessed directly and calls to TEE information are severely restricted ( I am not technical enough to elaborate on this ) and it's virtually impossible to get information from TEE // So, IMO, you can't

Master keys are stored by TEE. You cannot clone them. Some key material that is used with master keys can be found in /data/system. As long as you are not doing factory reset or wiping /data through TWRP & reinitializing the OS, TEE will not flush master keys.


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How do I make Android 11 stop removing a Wi-Fi certificate?
I'm using a Google Pixel 3a. A week ago, it was connecting all well to the corporate Wi-Fi which uses WPA Enterprise, but recently, it stopped.
In order to connect, I do the following:

Download the ca.pem file containing the CA certificate and the .p12 file containing the device certificate.
Install both CA and device certificates through Security › Encryption & credentials › Install a certificate › Wi-Fi certificate.
Configure the Wi-Fi to use those certificates.
EAP method being set to TLS, just as before.

As soon as I try to connect, it fails with no error message or details, and the CA certificate gets removed from the User credentials list (the ca.pem file is preserved). The behavior is the same no matter what I set in Online certificate status field (including “Do not validate” value that I can still use).
Why would Android remove the CA certificate? What do I need to do to make it stop doing that, and use the certificate to actually open the Wi-Fi connection?

Is the Wifi certificate that is removed valid (certification path present and valid + not expired)?

@Robert: the certificate is not expired. Regarding the validity of the certification path, how can I check it?

How to check the path of a certificate on Android . a good question. On plain Android I think this is not possible. There are a lot of app in Play Store that allow you to view certificates, but if the validate them?

@Robert: what about Linux? In fact, I'm not sure what you mean here by validity. This is a corporate self-generated CA certificate. The client Wi-Fi certificate is based directly on the CA one. Is Android expecting a certificate based on a public certificate authority now?

Google has made some changes for connecting to WPA Enterprise Wifi networks. See for example https://android.stackexchange.com/q/231859/2241 It is possible that those changes also the way how certificates are handled. Another reason could be that the CA defines revocation endpoints (CRL or OCSP) and Android tries to contact them but fails.


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Whatsapp not doing local backup restore! (not Google Drive)
Today I decided to reset the phone. I got all my backups. At the same time, I copied all the files of WhatsApp to my computer completely. now i copied Whatsapp folder to phone memory. I installed Whatsapp, I got a message on my number, then I gave permission to google drive for backups (I only store my backups locally, not on google drive) .. but no restore notification came. I don't have any messages! please help me what should i do
EDIT
When I uninstall and reinstall WhatsApp, the question 'Do you have a backup in google drive' appears. my whatsapp chat backup is locally on my phone. I tried every way. after installing i removed all google accounts, i copied whatsapp backups folder to both sd card and internal storage but it doesn't look at local backups...
please we need urgent support!

Hi, have you followed the steps given on the official WhatsApp Help Center?

Of course I tried.  The problem is that while whatsapp is re-installing, it only looks at google drive.  passes without looking at local backups
https://www.reddit.com/r/whatsapp/comments/np2zjp/how_to_restore_from_whatsapp_local_backup_not/?utm_medium=android_app&utm_source=share

There are similar questions asked already, and the most recent answer is to disable WhatsApp backup from Google Drive first: 1, 2. There's also the older approach mentioned on 3. Please try and let us know if any of it works. Thanks.

Yes, I've already tried all of these. it would also be approved if it worked. other than that, I installed the old whatsapp version (version 2.19.351) it said 'you have a local backup' (finally) but it didn't work this time. There is a really serious problem. I removed all my google accounts and did everything @AndrewT.

@AndrewT. Are you going to help me? I reset my phone. and now I want to do everything properly. Please help me.
a forum site

Sorry @theoyuncu8, I don't think I can help further. Looks like this is a relatively new issue since this site got the same questions recently. Hopefully others can help, and if you found the solution, feel free to also share it here.

A new topic has just been opened. I can't comment because I don't have 50 reputation but this problem is really starting to get serious. What can we do? Please guide us. https://android.stackexchange.com/questions/237495/whatsapp-cannot-restore-from-a-local-backup

Once OTP is verified, turn off intenet. This will force WhatsApp to look for local backup.

@defalt unfortunately. that didn't work either. Does it work on older versions according to what those who tried it said? Current Version: 2.21.10.16 Working Versions:  2.21.9.5, 2.21.8.17

Please install WhatsApp version 2.21.8.17 and try again. It did the job for me.


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Android file transfer does not mount Android internal storage
How could one mount internal storage of Android phone within the macOS terminal as a volume?

Hi, take note that questions directly asking for app recommendations are off-topic. Instead, we prefer the asker to just state the underlying problem that they want to solve and not putting any restriction for apps-only, so we'd appreciate it if you could [edit] the question, add some details and/or remove the restriction. Otherwise, you might be interested in our sister site, Software Recommendations Stack Exchange instead.

@AndrewT. If it needs additional editing, please feel free.


text:
Is it possible to fully restrict/disable apps when they are closed?
I would love to have more control over when apps can run on my Android: I wish that apps can't run in background, unless I whitelist them, or unless I am using them.
"Background Restriction" offers something similar. But it kills the restricted apps when they're placed in background: I can't simply leave them open, running in the background, until I close them.
For example, I want my music player to be fully dead when I'm not using it: I don't want it to run processes in the background. But when I'm using it, it should stay alive until I close it, even if its activity is not in the foreground.
This experience is very natural on desktop computers: most programs work while you leave their window open (background or foreground doesn't matter) and die as soon as you close it. I wish to have it on Android too, but Background Restriction doesn't quite offer it.
The "Recents Screen" seems like the perfect tool for what I need: only the apps in the Recents Screen (and those whitelisted) should be allowed to run. As soon as I remove one from the Recents Screen, it should get killed and become fully restricted.

Can I obtain my desired behavior by tweaking some configuration or by installing some software?

Otherwise, would it be possible to implement it myself? I think it'd be enough to have a tiny script listening to/polling the Recents Screen and toggling the Background Restriction setting for apps as they are added to/removed from the Recents Screen. Are there any APIs to do this available from e.g. bash or python, without needing to create a full fledged app?

I'm using rooted phones with Android 11 and the stock ROM (I have a Pixel 3XL and a Nexus 5X). A rootless solution would be better of course. I'm willing to change ROM, if that's a solution.

To be honest I'd say since Android was ment to be a do it all OS, the recents menu wasn't meant to work exactly how you'd want it to work. The folks developing the OS ar pretty smart and if it was as simple as just opening a process and terminating it when swiped out they would've done that.   Furthermore many times in Windows when you close a program it still runs stuff in th background.  Lastly, there exists some programs that force close apps when not in use but they bring many unwanted behaviors and in my opinion don't save that much battery.

Be aware that OEM's battery optimizers as described in: https://dontkillmyapp.com/ which act similar to what you describe break the API contract between the Android framework and developers, but as it is your intent - just be ready to accept that certain apps won't work correctly. It would probably help to know which phone/OS version you are running.

I would whitelist apps that I care about, trust and want them to work properly. But I also have a bunch of apps that I need to use for a short session every several days and I want these apps to be as dead as if they were uninstalled when they're not in use: music player (I only use it when travelling: a couple of hours every few weeks), app to control my camera (I use it maybe once a month), app for the vacuum cleaner (once a week for half an hour) and more. They keep some processes alive in the background. I don't want this. I would uninstall them every time, but un&installing is too slow.

I have two phones at the moment, a Pixel 3 XL and a Nexus 5x. Both rooted, with the stock ROM.

Stock ROM doesn't tell anyone which version of Android. Assuming you are using a recent/updated one on the Pixel 3 XL, look at App Standby Buckets via 'developer mode' & adb: https://developer.android.com/about/versions/pie/power#buckets and see if 'rare bucket' is acceptable.

Ohh, sorry, Android version 11.
I'll check out the rare bucket.


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Addon.d script on Android 11
Google introduced system_ext partition in Android 11 which can use system resources and can include system modules that:

Extend AOSP system modules in the system partition. We recommend upstreaming such modules to AOSP so they can be installed to the system partition later.
Bundle OEM or SoC-specific modules. We recommend unbundling such modules so they can be installed to the product or vendor partition.

I want to remove 2 folders named Snap and Gallery2 from /system_ext/priv-app partition. So, I created addon.d survival script to remove automatically every time I dirty flash a ROM.
The scripts commands are-
#!/sbin/sh
rm -rf "system_ext/priv-app/Gallery2"
rm -rf "system_ext/priv-app/Snap"

But the script is not working. Every time I dirty flash a ROM, I have to remove those folders manually.

echo "$(date '+%Y-%m-%d.%H:%M:%S'): $0 started" >> /cache/addon.log

create some log via your script to confirm your script is executed at all. beware partition has to be mounted

also you should use absolute paths (leading / )


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How to disable autorefresh on Android?
I'm using Resurrection Remix Tissot 7.0.1 (Pie) in a Mi-A1 and I'm looking for a way to disable autorefresh on my apps, someone know how to do it?
The "autorefresh" is the function of Android that refresh an app (like Firefox Browser) always you change it from second to first plan, and I see this as a wasting of time, of data, of processing time and of battery life.
If I'm writing something in a comment box on Firefox, for instance, when I change the browser to second plan to confirm some information and come it back to first plan, it refreshs the site automatically and I lose everything I've written.

Firefox for Android is a buggy piece of software. Its private browsing is worst. One version it was working fine. Then I updated it and suffered the same symptoms mentioned in your question. If the problem is limited to Firefox only, report it to Mozilla. If not, you may be running short on RAM.

I owned this phone earlier, it had this problem on stock Android 8,AFAIR

Firelord, it happens on all apps. What are you mean about "running short on RAM"? I believe my RAM is in a normal behaviour.


text:
Is there an option to block local network access for apps?
I'm trying to prevent apps from accessing other devices on the same network (LAN). Something similar to this iOS setting.

Some searching led me to this feature in Express VPN.

Is there a way to do this in Android Settings or using a non-VPN app?

My LAN is protected by firewalls. That's the only real solution if you want a real protection. Each computer on the LAN can have its own firewall preventing connections from the outside. Only let the very connections you are interested in happen (if any, I like to have access to my local Apache2 where I store some info. I like to access).
It will always be possible to circumvent protections on a phone if you're a good hacker. Firewalls on the other end requires a possible hack to penetrate that computer, somehow. Not very likely if you do not have any services (completely block all traffic) since that would mean an exploit in the firewall/network stack.


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Trying to root Pixel XL
I'm trying to root a Pixel XL in order to use 'su' in an adb shell to run gdbserver.
I've unlocked a few other phones to do this but the process seems a little different now or it is for this particular phone.
I've followed the instructions at 'https://www.online-tech-tips.com/smartphones/how-to-root-a-pixel-xl-2-2xl-3-3xl/' but I'm stuck at the command 'fastboot boot twrp.img'.
I downloaded the version of TWRP for my device (twrp-pixel-installer-marlin-3.3.0-0) but there's no file called 'twrp.img' in there. There's not even a file with a '.img' extension, just these:
magiskboot
META-INF
ramdisk-twrp.cpio

Now, I'm a bit overly cautious when it comes to flashing a mobile phone and I don't want to put a bunch of junk in my bootloader, so what should I do here? It's not particularly clear (and when it comes to potentially bricking things, I very much like things to be clear).

Why do you download the installer from 2019 if you want the image from 2021?

Like @Robert said you have the latest (April this year) released zip adm img files here https://dl.twrp.me/marlin/

Ok, so the list wasn't sorted by date, they changed the naming convention for some reason and I missed the later files: oops.
However, opening up
twrp-installer-3.5.2_9-0-marlin.zip
reveals exactly the same problem.
magiskboot
META-INF
ramdisk-twrp.cpio
nothing with .img in there that I can see.  Is that 'cpio' file the same as an img file? It's not something I'd like to guess.

Why are you opening zip file - there are twrp.img files in the same list. This looks to be the latest https://dl.twrp.me/marlin/twrp-3.5.2_9-0-marlin.img.html

I opened the zip files because that's typically what you do with zip files.  If the img files are a direct download, what are the zip files for?
Like I said, apologies if I'm appearing dense here but I'm super cautious when flashing the phone, I don't want to make any mistakes.

Please read the full page before downloading something. There are three different types of downloads on this site.

Ok, I didn't realise that. I don't recall having to use TWRP for rooting with other phones, although it looks like a useful program that should help my android dev work. Thanks for your help and patience.

indeed the sorting of download list is quite confusing, scroll down for twrp.img

Does this answer your question? Why can't I write to recovery using fastboot on A/B device?


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How to activate band aggregation all thee time when available (4G+ at all times)?
The 4g+ network only activates when network is under big load.
I'd like to have 4g+ activated as soon as it is available and as long as it is available.
Does anybody know where I can change the aggregation settings ?

Are you taking about multiple 4G links or the combination of 4G+5G? Which phone do you use?

I mean multiple 4g links, I'm using a one plus 7t pro it runs fine but only activates on network load


text:
Mass uninstall apps
My phone is massively cluttered - I've got something on the order of 50 (!) apps I am not using at all. I could manually uninstall them, but the wait for the uninstallation to finish between selecting the next one would drive me crazy.
Is there a way to, at least, create a list of apps to be uninstalled all together? I'm not afraid of using ADB, but don't want to root the phone. I'd also prefer not to use 3rd party apps.
My phone is Xiaomi Mi A3 (Android One), with Android 9.
Order of preference for methods:

Google Play on PC (website)
Phone settings or similar (no 3rd party app)
ADB or other debug interface, without rooting
3rd party app

ADB (no root needed) should be possible as per Bulk uninstall applications. The "Google Play on PC" method seems to disappear around/before 2014 though.

@AndrewT. thanks, that should work. I'd say this is a duplicate, but the linked question is 10 years old.

This app works well. Though 3rd party apps aren't preferred by you https://play.google.com/store/apps/details?id=com.splendapps.shark

I would approach this from a different direction, to backup the data from the phone you want to keep, then do a factory reset which will effectively remove all the apps and allow you to reinstall what you now require.
It will also remove any orphaned data and folders that uninstalling the apps could leave behind.

that's how i would do it too

Accepting, since this is what happened in the end - I bought a new phone and only moved a few apps over.

Using the python tool AMDH, that use ADB, with the option '-l' (list applications) with the argument '-t e' (list all enabled applications, including system apps) will list numbered installed applications by package name. You can select applications numbers separated by comma and choose the action uninstall ('u'). Uninstalling some system apps can break your system, you can use disable action instead of uninstall if you are not sure that the application is mandatory for the system.


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Why should I care about ROM size when buying a new 'phone?
RAM is clear enough, but why so many different ROM sizes & how much does a basic user need?
Basic == 'phone calls/WhatsApp/SMS/email/light browser use - no games, streaming, videos, music,

That mainly depends on how many attachments you receive e.g. via WhatsApp and email and if you keep them all. If you don't store everything or e.g. use IMAP for email (server stores everything, client just keep temporary copies) the you may work happily with an 32GB or even 16GB flash device. BTW: ROM means "read-only memory" - I think you mean flash memory, because a read-only memory would be of no use to you...

Hmm, apparently what's called "ROM" is actually the storage capacity (equivalent to harddisk), though I believe it's actually a misnomer since it's not "read-only memory" (as it can be writable).

@Robert I actually meant ROM. I can understand why more RAM is better, but am not so sure about ROM

Please explain what's your understanding of word "ROM" is in the context of Android phones. Are you talking about the internal flash storage (which is like 32GB, 64GB and so on)? Or are you referring to the custom operating systems which are developed by community for a device (wrongly called ROMs because they are written to /system, /vendor partitions which aren't writable for user data unlike /data partition)? Technically speaking there's no ROM on Android devices except some tiny part (usually a few KBs) embedded with SoCs which includes Boot-ROM (or its equivalent) like BIOS on a PC.

Does this answer your question? 2 GB RAM or 3 GB RAM, does it really matter?

As a prior post indicates you use a
Ulefone Armor X3
A quick search brings up:
https://www.amazon.com/Smartphone-Ulefone-Armor-Waterproof-Shockproof/dp/B07VL28Y84
And in the description reads:

2GB RAM + 32GB ROM

This is an error in the description. It should read

2GB RAM + 32GB Flash storage

That Flash storage is the same as a hard drive and will contain the OS and apps/data/pictures/videos that you are using.


text:
Why won't my saved home screen shortcuts open?
Today, I turned on my Samsung Galaxy S8 and all the shortcuts I "saved to home page" won't open. The shortcuts are now gray on my home screen. When I click on one, an error pops up that says "App not found".

These aren't downloaded apps. These are websites and web pages I saved to the home screen for later reference. Newspaper articles, local cleaning services, stuff I "saved to home page".
Yesterday was the changeover from Samsung Cloud to Microsoft One Drive Cloud, (I think). Could this have something to do with it? I changed over to One Drive last week.
Any help would be appreciated.

Those links are connected to your web browser app (Samsung Internet or whatever web browser you used for creating the links). Warning: clearing the app data of that web browser will result in all links being deleted.

Thankyou Robert. I actually restarted my phone and they all just came back. So...problem solved! Thankyou for your reply though!!


text:
Whatsapp - Cannot restore from a local backup
today I made a mistake on my Samsung Galaxy note 10+ Phone: my daughter deleted the app.
When I took the phone back, I noticed that whatsapp was no longer more installed on my phone.
When I reinstalled it from play store, activated, it can't find any backup, even if I have daily backup on my phone.
I've a lot of files in my whatsapp chat history and I reinstalled several times, following also the steps described in this guide: WhatsApp doesn't prompt to restore from local storage, but none of the solutions provided (permissions, etc.) works.
At first startup, Whatsapp asks for the permission to access google drive and then, it asks for the name to display, skipping the backup. Please note that i never changed my phone number, etc.
I tried also on Xiaomi Redmi Note 7, that I just initialized for this purpose.
I copied all the whatsapp data folder, renamed the appropriate msgstore.db.crypt14 but whatsapp didn't ask for any restore.
At this point, after several retries, Whatsapp activation system let me wait 24 hours or days to receive a new activation code by text message or call.
I've all of my working history and backed up whatsapp folder several times, during years but I never experienced a behaviour like that.
Any help would be really appreciated.
Thanks in advance
Digitalchild

With A11 WhatsApp new location is
/sdcard/Android/media/com.whatsapp/WhatsApp/DataBases

Try to copy DBs to here


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Why can't Microsoft teams see my camera's content on my Samsung Galaxy S9?
Microsoft Teams does have access to the camera:

But Microsoft Teams doesn't see anything on my camera:

Why can't Microsoft teams see my camera's content on my Samsung Galaxy S9?
My default camera can see my two cameras' content without any issue.
Switching between the two cameras didn't help. The two cameras have the same issue in Teams.
Rebooting the phone didn't help.

Do you have some permissions Manager installed, such as some appops app or XprivacyLua? Those apps might  be autoconfigured to deny camera access to apps until explicitly allowed by the user. Otherwise, have you tried clearing data of Teams app? Is this a sudden problem or has Teams never been able to access Camera since its installation? Since when did the problem start? Any update to system or Teams app after which you observed this problem?

Can other apps (other than the default camera and Microsoft Teams) use the camera?