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How do I know if my phone's touchscreen supports Electro Magnetic Resonance (EMR) technology?
I am planning to start sketching on my Android Device - Nokia 6.1 Plus - using Apps like AutoDesk SketchBook, Bamboo Paper or Adobe Sketch. For that I am thinking of buying a stylus - Noris Digital.
Noris Digital only works if the touchscreen has electromagnetic resonance (EMR) digitizer. I am unable to find out if my mobile device has that feature. Any idea how do I find that out.
If my phone does not support that then can I use Wacom's Bamboo Tip, again the issue is finding if its supported or not. Moreover this does not have pressure levels. How do I know which pressure level and palm rejecting stylus will work for my phone.

Related on Android's touch pressure: Why isn't the touchscreen pressure reading being put into use by Android? which basically says "Android doesn't support real touch pressure natively and instead approximating the area of the touch", which leaves to the drawing app to communicate with the stylus directly for pressure value (if possible). (Also related on GraphicDesign.SE: Android tablet vs Wacom tablet)

Maybe this [app](Complete information about your CPU, GPU, battery, camera, network and OS.
Available on Google Play: https://play.google.com/store/apps/details?id=flar2.devcheck) would tell you if it is supported?

If you scroll down on your linked page to the Noris Digital stylus, there is a section on compatibility which links to this pdf document
The only mobile device I recognize are the Samsung mobile devices supporting S-Pen.
Your alternate Bamboo Tip link also has a compatibility document: https://www.wacom.com/en-us/comp which lists support on all of Bamboo's devices. The Bamboo Tip section lists a number of Android devices: like the Google Nexus 5X, Amazon Fire HD 10 (7th generation), Samsung Galaxy S8 as well other manufacturers. This tells me that the Bamboo Tip is capacitive and should work with most phones (unless using the older resistive screen for speciality devices).
As to how the Bamboo Tip can handle palm rejection, I can't be sure, but expect that it is still limited to what the device is capable of, as app developers typically depend on the system to handle errant touches.

I did read the pdf document. It's not possible for them to test each and every smartphone out there. I think they just have a sample of supported devices. In the pdf itself they mention that if the device has EMR technology then you should be good. So I am focusing on that. How common is it? And how do I know if my phone has it. My research tells me that it is used for pressure sensitive strokes. So is there a way to find that out from a smartphone itself?

EMR to my knowledge is a pretty specialized tech for phones. See How do Samsung S-Pen work and that tech has to be licensed to manufacturer from Wacom . Even the FAQ at the Noris Digital site calls it 'Wacom EMR' and makes a comparison to 'S-Pen'. Remember if the device has a Pen with pressure sensitivity that is a marketing point for the device and so would be a candidate.


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How to fix "Unfortunately, com.android.keyguard has stopped"?
Every time, after booting up my device (UbiSlate 7Cz), I receive the following error message with a black background:

Unfortunately, com.android.keyguard has stopped.

When I tap "OK" below this message, the dialogue box quickly disappears and reappears again. I'm unable to access anything on my device. So, opening the settings app and following the steps outlined in this thread is out of my domain.
However, I managed to open my device in recovery mode by pressing the power and volume up buttons. Even after executing the following commands in the recovery mode:

wipe data/factory reset
wipe cache partition

and rebooting the device again, there was no improvement in the situation.
Other options, I get when I press the power and volume up buttons are fastboot mode and normal boot. When I chose the fastboot mode, the device just displayed the default start-up screen. As it was showing the same stuff even after hours, I used the reset pin to turn the device off (the power button didn't have any impact during this regime). From here, I am able to do the same steps as mentioned earlier. But even after all this, the device just shows this particular error message.
While searching this site, I found this question How to fix instant lock “unfortunately com.android.systemui has stopped” on Moto G with ART which I found to be similar to that of mine but with a different error message. I find my question to be different from that because, my device didn't have ART and I'm unable to view anything unlike the OP there, who could see some apps and widgets on the home screen. Also I have a feeling that different error messages have different methods to fix.
I also had a look at these threads - How to fix "Unfortunately, the process xxx has stopped"?, and How to fix "unfortunately , the process com.android.systemui has stopped" error?, but none of the methods described in the answers resolved my issue.
It would be very helpful if you could provide any solutions to this problem.
Thank you in advance!

Please add more details to your question: What Android version, what device, Stock ROM installed, is the device rooted?

@Robert: I've added the name of the device and an official webpage giving all the specifications. Apart from that, the usual details I see under the settings is currently inaccessible. Could you tell whether this is sufficient or not? Thanks!

The device uses Android 4.4.x, hence it seem to be pretty old. May be the flash memory got corrupted or a virus has infected the system. The only way I see to recovery the system is to fully flash a complete system image. However I don't know here to get one. If there is a custom ROM for your device this would also be an alternative. Check XDA if you can find a ROM for your device.

My solution: the error happened only when I entered a new SIM card. Without SIM cards the phone worked as expected (Alcatel Pixi 3). I had to disable sim pin using another phone, and then transfer the sim back to the mobile phone with the problem. Disabling sim pin check seemed to solve it.

** Clear Data & Catch of the App

Option 1. Long Press the Keyboard App & Go to Storage and Clear Data

Option 2. Go Setting -> App -> Keyboard -> Storage -> Clear Storage.

source: Stack Exchange

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

sort: votes


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Where can I find the bootanimation.zip in the Evolution X Custom ROM?
So, I wanted to replace the stock boot animation that comes with Evolution X since it is kind of boring, but the problem was that I couldn't find the /system/media/ directory in any root browser or even the file manager built within TWRP. I just need to know where I can find the bootanimation.zip file in Evolution X, and if there are any further steps required to change it other than just backing up the original boot animation and replacing it.
Specifics: I'm running the latest official build of Evolution X for zerofltexx (Samsung Galaxy S6) with MagiskRoot and a few Magisk Modules.

Try to do a search in the root explorer.you will get the location
System/product/media
Thanks
-redminote5pro
-evolutionx 4.3

Thanks! I'm guessing I will have to replace bootanimation-dark.zip as well as bootanimation.zip?

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


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How to use multiple physical keyboard layouts on Android Oreo 8.1.0 Go Edition phones?
After connecting Bluetooth keyboard to my Android phone, I can't add more than one physical keyboard layout. Here is the picture

I mean, using the Ctrl + Space shortcut that has multiple physical keyboard layout options, I can't. My Android phone version is 8.1.0 Oreo Go Edition.
I can't even use the Android system keyboard shortcut!
Example: Notification is displayed by pressing search + n. But pressing the shortcut key is not working.
Here is the picture

May be irrelevant, but I had the same issue on MIUI 12.0.4.
Seems like Layout selection menu is bugged, but there is a workaround. You need to glitch menu to actually select layouts. Try turn on and off rapidly multiple layouts in couple of seconds (two are usually enough, just one is also works, but much rarer), and after leaving this menu and coming back you can see some of them switched.
In my case after ~10 attempts I managed to enable only layouts I need (English and Russian). They still doesn't display them in layout selection though, but now i can switch them with Cmd(Win) + Space


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Tap on Picture in MMS and a different picture opens up?
I will receive a picture in an MMS on my Lg Thin Q.  When I tap on the picture to enlarge it a completely different picture associated to the person who sent this one opens up.  Any suggestions on how to correct this?

It is a known bug with the MMS in SOME LG smartphones where the older version of “Messages” app is installed. Previously deleted MMS picture shows up in newest incoming MMS message instead of the intended image due to this bug.
You can fix it by updating the "Messages" app to the latest version.
Source: https://www.lg.com/ca_en/support/product-help/CT30014940-20150929584034


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Internet Access unavailable in browsers and mail. But Youtube and Google Play worrk fine
[EDIT] after further diagnosis I observed that I am unable to access my router via its (local)ip address in chrome but I am able to access my router via edge browser.
Chrome in my android device is unable to access any website(can't open this page error) but at the same time, it works in the Microsoft Edge app. The chrome gives some suggestion link but when I click on the suggestion link a screen overlay comes up Similar to the image below, but the overlay quickly vanishes(I suspect whatever process was called, it crashes).
I observed similar behavior in my Gmail app, when I load an click on an email it tries to open it and quickly crashes(after showing loading similar to the image below). Although I am still able to open attachments in Gmail app.
Almost all other apps like youtube, google play are working nicely.
I am using an Android device with Android Pie(9).
This problem happened Suddenly whilst the phone was idle.
I have tried disabling these apps, clearing storage, starting in safe mode.
Chrome error:

Loading screen after which crashes take place look something like this:

Please show us the error messages you get in the web browser(s).

@Robert I updated the question, when I click on learn more. An loading overlay occurs and the overlay crashes and I am back to this "can't open this page screen".

I have now disabled my chrome browser and which has allowed me to use Gmail and other apps that were crashing.
There is some problem with Google Chrome App, which leads to other apps crashing(maybe they use chrome[or its API] as a default backend).


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Running an rsync server on an Android device over a non-WiFi, cell-based connection?
I asked a somewhat similar question to this recently (see Rsync-like downloads over adb?), but what I'm asking here is a little bit different.
Also, if this question belongs in a different forum, I apologize in advance, and am happy to repost it elsewhere.
I want to set up an actual rsync server on my Android device, but one which works without a WiFi connection. In other words, I want it to work over a normal "cell phone" data connection. The only ways I've been able to get an rsync server to work so far is over a WiFi connection.
I know how to determine the device's assigned IP address in real time (even with a cell-based, non-WiFi data connection) and how make that IP address available to sources outside of the device. But I haven't been able to get the device to listen on that specific IP address when I do not have a WiFi connection.
Does anyone know if this is even possible?
Thank you in advance.

Does this answer your question? How to connect to Android through SSH over 3G/4G public IP?. If it is an ssh or an rsync server does not matter, as you usually don't get a public IP in the cell phone network you can't access your device from outside.

Actually, the topic you suggested does address my question, so I will move over to there. Even without a public IP, there might be a way to accomplish this via port forwarding to a proxy -- or something similar. I'll ask under that topic. Thank you.


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ES File Folder Remote Manager is disconnect by auto?
I am using ES File Folder for exchanging the file from Mobile to PC.
The issue is , the Remote Manager is automatically disconnected in times.
I want to manual set to Start (the connection) and to Stop the connection. Is there is any way to achieve this ?

Is there an issue in using MTP via USB cable for file exchange? It is plain and simple.

No, not using USB. The mobile is connected thru Wifi


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How do I enable a forced stop & disabled Bluetooth Share app on Android 4.0.4 (Ice Cream Sandwich)
Over enthusiastic to disable many distracting apps on my Sony Xperia U (ST25i) I went "settings>apps>all" and disabled away.  Where no disable option was available, I clicked on force stop.  With Bluetooth Share I stupidly took it to be a social networking app and disabled it, later force stopping it.  Dumb, I know, but how do I get it back?  I'm fairly new to all of this, obviously, so please be very specific in responding.  Many thanks.

Click the "Enable" button that is located at the same point where you clicked "Disable"?

Thanks Robert, but clicking "Disable" and "Force stop" buttons extinguished their lights and made both inoperable. "Disable" did not change to "Enable". Clicking a button with an extinguished light does nothing, of course. But installing Syncios Manager to allow my Xperia and PC to talk has, at least, brought the "Force stop" button light back on again. The "Disable" button, however, remains dead.

For apps that are forced stopped, locate them in the Play Store and click Enable button to enable them.

I think you mean For apps that are disabled and not forced stopped.


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Smoothing active capacitive stylus lines, LG G pad X
No idea if this is the right place to post this, since I don't know if the problem is my OS (android 6.0), stylus (Xiron active capacitive), software, or screen. My stylus makes very jerky/wavy lines, especially when slow and diagonal. However, it works ok with the passive capacitive end of it or best just my finger. The only app that seems to smooth this is Bamboo Paper. But, I need to annotate PDFs, which bamboo cannot open. Do i have a faulty pen? Is there better software that I could use? Pics below of finger vs stylus in bamboo and adobe reader.

Long time ago I owned a Note2, whose Stylus had similar issues. Dropping it on a firm hard surface like on carpet with the stylus end hitting the carpet was one solution and that actually helped. It could be opened up easily and the potentiometer adjusted to increase /decrease sensitivity. See if you can do this on your pen or try the tapping on firm surface method repeatedly and see if it helps

You can try apps specifically meant for pdf like this or this

@beeshyams thanks, but sadly hitting the tip didn't help. I tried those two and many others, and the only program that seemed to work ok was INKredible, but it's still just a little jerky/the resolution of the writing is so low to the point of frustration.

Xiron lacks pressure sensitivity ; maybe this is the reason?

Wiki says active pens are expected to detect more than 8000 pressure sensitivity levels and if Xiron doesn't have this feature, this could well be the reason for your frustration. On bamboo paper app, you are not seeing this, because it is specifically meant for stylus writing and compensates, resulting in smooth lines unlike a pdf (no proof, but sounds logical to me)


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Does Android Oreo Go support tethering?
I want to get a cheap Android Go phone for wifi-tethering purposes as the battery is acting up on the cheap Argos Bush Hero 5.5 V3 AC55SEDCV2 phone I  use for that purpose.
Does Android Oreo Go support tethering? Because it is supposed to be an Android 8.0 with reduced functionality I have to check before I commit.


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Office Mobile not installed yet opening PDF files
I have a Samsung A50 phone, stock Android which came with the device (from Comcast), everything up to date and not rooted. I have not registered for the Samsung Galaxy store or whatever is called, and therefore never installed anything from it.
I never installed Office Mobile on my phone, and looking at the list of installed apps in Google Play shows no Office Mobile.
Yet, starting today, attempting to open some (but not all!) PDF files (by tapping their name in the Document folder) opens them in Office Mobile rather than the "Google Drive PDF viewer" where they did open till the day before yesterday (I did not try yesterday).
There is not an option to force opening the files in "Google Drive PDF viewer". For a test, I installed the "Google PDF Viewer" (I wish they chose less similar and less confusing names). After that Android allows me to open the files with "Google PDF Viewer", but it fails with "Cannot display PDF (no file received)". After a reboot, the files were gone.
What may have happened? I can guess that the files corrupted and the "Google Drive PDF viewer" magically knew (and therefore was not proposing itself to open them), whereas the other two apps did.
Yet, why is there an app which I never installed and does not show up in the list of installed apps? Heck, if I search for it in Google Play, I even find it, and it shows me the option to install it!

I had something similar on my Sony XA2, but I only got a question if I want to open the PDF file in some Office app (I think it was the same app you are talking about). The dialog that popped up was not the default Android app selector, hence I was assuming that this was some built-in advertisement for a special app added by Sony. May you also got such a dialog and have clicked yes and therefore automatically installed it. Or it came include in an Android system update.

1.When searching for apps. Tap the menu  hamburger, items on the right, then tap show system files etc.
It should be in there. From this you can go into the application information and clear everything especially "Defaults".
Or
2. However, you can try this
https://play.google.com/store/apps/details?id=com.aboutmycode.betteropenwith
Or just simply install office and uninstall it after you have demonstrated step one.
Good luck


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How can i fix "this rom is for A5ulte, a5ultxx... your phone is" + CUSTOM ROM FOR SM-A500FU ANDROID PIE
I have Resurrection remix 7.1.2 installed on my SM-A500fu and it worked perfectly. I have been using it for some time now till I recently discovered an upgrade of the same custom rom (resurrection remix 9.0 _android pie) for SM-A500FU. I downloaded and flashed through the right process. wipe cache, system etc.. When I try flashing the upgrade via twrp recovery, I keep getting an error message saying that the rom is meant for a5ulte, a5ultexx...it goes on to list other codenames...and at the latter part it says "my phone is" but doesn't state my phones codename.
I need help please.
Has my codename changed due to my previous ROM?
how do I know my current codename because when I boot to the download mode, my phone's model is still SM-A500FU?
Is there a way to work around it? please urgently.
mimbogel@gmail.com

check your phone model from download mode. edit your build.prop or default.prop with right phone model, or modify the installer script to skip the model check


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Unable to take kernel logs on a non-rooted device
I am trying to take kernel logs but so far have only got errors like 'permission denied', 'path does not exist' or 'kernel log does not exist'.
I have tried this kernel panic link, this crash logs link, this link that suggests how to take logcat and kernel logs simultaneously,the kernel log option in this secret menu, this link suggesting console-ramoops,this XDA tutorial and several other links.
List of commands tried:

cat /proc/last_kmsg
dmesg
cat /proc/kmsg
cat /dev/kmsg
cat /sys/fs/pstore/console-ramoops
*#9900# (Samsung only)

I am doing this in response to a comment on this post of mine. Any suggestions?
Edit:
So I have been able to get logs using *#9900#. The kernel log option didn't work but I set debug mode to high, let the reboot happen and then used the inbuilt option to copy logs to storage. The device restarted and showed 'watchdog reset' after which I force restarted. Along with many other files, texts, logs, it has mention of /proc/last_kmsg in a txt file. I will see if it is useful and share in the original post.

@IrfanLatif I have just been successful in getting the required logs using option 6 mentioned in post. Your link looks interesting and I will give it a try too tomorrow. Thank you.


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How do I flash stock Android rom on my Nokia 2.1 - to which I've forotten both PIN code and Google credentials?
So I recently inherited a  Nokia 2.1 from a relative who passed. I don't know the pin code, nor do I know the Google credentials 0needed.
When I enter recovery, Fastboot mode is not selectable and is in red text comparet to the other text. I did manage to get ADB to recognize the device in sideload mode, but when I try flashing the stock Android rom i downloaded it gives me the error message: "Signature verification failed (Error 21)".
So I can't enter Fastboot for some reason, so I can't use Fastboot to flash TWRP and after that flash my ROM, and  I can't use sideload to flash because of a sinature verification error.
What do I need to do to be able to flash TWRP/a stock ROM and get this phone running again?
Thanks

does the device boot normal? what rom is installed (stock/custom)?


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Camera stops recording (but doesn't crash)
(Phone: Samsung Galaxy A5 (2017))
Since a few months back, every time I try to record a video with my default camera app or any other third party app, what happens is the following:

I start the recording.
A timer starts at the bottom with a blinking red light to indicate that the phone is indeed recording.
In a random amount of time (half a minute up to 3 minutes) the red light disappears, the timer stops, but the camera doesn't crash or anything - it just stays frozen and stops recording. I have to exit the app and reenter to get it working again.

Additional details:

Photos I can take just fine.
The problem doesn't seem to affect Snapchat or Google Meet, which I both regularly use.
Yes, the problem also occurs with the front camera.
When I tried to record on another application, when it stopped recording it stated "Failed to reconnect to camera" and "Server died, video halted".

What I have tried so far (and not one has worked):

Deleting app data/cache
Restarting my phone
Changing between SD and internal storage for the saving location
Going into safe mode
Factory restarting my phone twice - once after I had restored everything, second time when the first thing I did after setting up my phone was going into the camera app to record.

I'm unsure if this is the right place for this question, but any help at this point would be much appreciated, as I'm in a big need for a recording device currently. Thanks!

In safe mode, does the stock camera work as it should?

Nope, still stops the recording process, even after the factory reset.

Did you check if the hardware (Camera) is OK? There are many apps on Play Store for "hardware tester", "phone tester" or "camera tester". This one is specific to Samsung. Maybe more. This is also a general purpose good app for Samsung https://play.google.com/store/apps/details?id=org.vndnguyen.phoneinfo


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How to multiboot 2 Android-X86 distro? (for instance PrimeOS and Bliss OS)
How to multiboot 2 Android-X86 distro?
I tried to make a dual boot with Bliss OS and PrimeOS.
I installed Bliss OS to its dedicated partition on my hard drive.
It was perfectly booting and working.
Then, I installed PrimeOS.
It was perfectly booting, but it changed the GRUB config and made it only possible to boot Prime.
I reinstalled Bliss OS, same thing.
I edited the GRUB config files, as mentioned here: https://unix.stackexchange.com/questions/492587/add-prime-os-android-x86-x64-to-grub-menu/519867?noredirect=1#comment1090351_519867
It seems only one of the occurrence of an Android-X86 ISO is able to boot in a given system.
How to fix the config file to boot several of them?

The way android_x86 treats EFI GRUB config is buggy or misunderstood. No matter what android_installation you choose from grub it will just boot the first found android system on the hard drive (and it seems that device.map that causes the pain).
Anyhow here is a workaround that I did to get stuff working:
I wiped 1 of my laptops for that (MacBook Pro 8,1 320GB hard drive)

Installed Linux (Kubuntu) choosing the whole hard drive as one part + efi
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 298.1G  0 disk
├─sda1   8:1    0   512M  0 part /boot/efi
└─sda2   8:2    0 297.6G  0 part /

Installed PrimeOS choosing sda2 (DO NOT FORMAT),
ignore EFI installation (optional)
Booted into Linux again and renamed primeOS installation folder
sudo mv /android /primeOS

Installed Bliss OS the same way as PrimeOS + choose /system to be rw
Booted into Linux again, renamed Bliss OS installation folder
sudo mv /blissos_x86.xx.xx /blissOS

While still on Linux added both Android installations to GRUB by adding the following lines to /etc/grube.d/40_custom
submenu 'Android' {
    menuentry 'primeOS' --class android  --class android-x86_64 --class gnu-linux --class os {
        set root='hd0,gpt2'
        linux /primeOS/kernel root=/dev/ram0 SERIAL=random logo.showlogo=1 androidboot.selinux=permissive quiet DATA= USB_DATA_PARTITION=1
        initrd /primeOS/initrd.img
    }
    menuentry 'blissOS' --class android  --class android-x86_64 --class gnu-linux --class os {
        set root='hd0,gpt2'
        linux /blissOS/kernel root=/dev/ram0 SERIAL=random logo.showlogo=1 androidboot.selinux=permissive quiet DATA= USB_DATA_PARTITION=1
        initrd /blissOS/initrd.img
    }
}

Updated GRUB on Linux sudo update-grub, and made sure the tail of /boot/grub/grub.conf contains the Android entries
Rebooted and chose one of the Android installations and I meet an error telling me hd0,gpt2 not found bizarre o.O ,  after a bit of googling it says that it happens when running grub-install before generating or coping device.map to /boot/grub!
To fix that I had to go back to /etc/grub.d/40_custom and change hd0 to hd1 in my case

NOTE for small hard drives like mine it's better to use one partition (ext4) shared between Linux and Androids, from all systems you enjoy the full free space.


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Way to prevent the noise when 2 phones together
In using an app, for example Wechat, to have video chats.
Two Android phones A and B are sitting in the same room. The two users of A and B stated video chat with mobile phones C and D in another city, when two users of C and D are also sitting in the same room.
That is, phone A is calling phone C; phone B is calling phone D.
When the video chats started, because phones A and B,  C and D are close to each other, sharp noises started to appear.
What's the way to prevent this noises in the video chats?
Thank you.

This phenomenon is called audio feedback which usually occurs when the sound from the speakers reaches back into the microphone, and then gets amplified because of the speaker-mic loop.
Common and general solutions are to cut off the loop, or at least reduce the loop gain by:

Wearing earphone or headphone (isolate the speaker and the mic, prevent the feedback loop completely)
Mute the mic when not needed to speak (prevent the chance of feedback loop)
Reduce the speaker volume (reduce the volume gain)
Take some distance between the speakers (reduce the volume gain)

Considering this is a physical phenomenon, I'm not sure if there are Android-specific solutions, though I'm also interested to know if there are... consider posting it as the answer!

The phone "knows" the sound it is emitting from its speakers and could thus subtract that from what it is recording on the microphone. This is similar to echo cancellation. This would be one thing that can be done in software. Other than that, the basic "acoustic hygiene" techniques you listed are the most effective. No need for complex feedback suppression algorithms if there is no feedback to suppress!

@JörgWMittag Such subtracting would not work when two phones are involved.

Before feedback cancellation techniques became common, such an effect would happen even with one pair of phones, e.g. phone A calling phone C. If both phones are on loudspeaker, then the signal emitted by the phone A would go into A's microphone and get transmitted to the phone C, where the same feedback between the loudspeaker and the microphone would re-transmit it back to A, etc:
SPK_A -> MIC_A -> SPK_C -> MIC_C

This problem is prevented by subtracting the loudspeaker output signal for the microphone input. However, for such a software subtraction to work, phone A needs to know what to subtract: if A is the only phone in the room, it can subtract its own loudspeaker output, and feedback cancellation works as intended.
With a second pair of phones, feedback cancellation fails because the signal emitted by the phone A is picked up by the phone B instead. As the phone B doesn't know what signal A was emitting, it cannot subtract it from its microphone input, and sends it to phone D:
SPK_A -> MIC_B -> SPK_D -> MIC_C

There is a second (symmetrical) feedback loop that is possible:
SPK_B -> MIC_A -> SPK_C -> MIC_D

As you can see, the loops are closed, and there is no opportunity for the feedback cancellation software to break those.
In order to prevent the noise, you'll have to break the cross-phone loops physically, e.g. by muting both loudspeakers (switching to earphone) in one of the rooms (e.g. A and B), or in one of the calls (e.g. A and C).
Indeed, muting the microphones, being in separate rooms or having a single call at a time would also help, but I suppose those are not real options.

This depends somewhat on the implementation of the feedback cancellation - you can also reduce gain automatically/adjust a notch filter if an increasing high frequency component is detected, which is how units such as this work https://www.behringer.com/Categories/Behringer/Signal-Processors/Feedback-Suppressors/FBQ100/p/P0A3Q#googtrans(en|en) but I don't know if that approach is implemented on 'phones.

@PeteKirkham Suppressing high pitch with a filter will only work when the feedback delay is fixed and very small (single digit milliseconds), such as between a microphone and loudspeakers on a stage. Mobile phones can delay audio for hundreds of milliseconds, which means you'll have to filter out the whole audio range to eliminate the feedback.

It's been a long time since digital signal processors were capable of both detecting the peak frequency of a spectrum and implementing a narrow filter at any point in the audio range. Both were part of the course work when I did my first electronics degree in the late 1980s.

@PeteKirkham If you filter out, say, 10 kHz, what will prevent the feedback loop from running on 10.1 kHz? If the problem is so easy to solve, why do you think cell phone manufacturers didn't solve it already?

The professional systems such as the one I linked to change the filtered frequency when they detect a change, otherwise they would be useless as the frequency changes when people move on stage. If you think about the OP, it is a situation which only occurs when there are two phones in the loop, so doing the development work would not benefit most customers, hence you see the approach in recording equipment and conference calling systems rather than phones, where the subtraction technique works well enough for most use cases.


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Relocked bootloader
I had unlocked bootloader on Moto g5s, and then relocked it again with  fastboot oem lock, now it shows warning "Your device has loaded a different operating system" and when turned on, asks a password
is it a brick now?
How can this be solved

@alecxs, I actually failed the password as many times, that it made hard reset... I couldn't do even hard reset via recovery mode. So, as far as unlocking it again, I have tried but it says 'invalid boot state', and does not unlock.

what kind of password protection, are you talking about FRP? how do you know bootloader is locked, and how is the bootloader warning message related to password protection?


text:
Control camera from another phone
I have a phone on a camera stand. Is there any way to turn on and off recording from another phone?
I also want to trigger taking photographs.

You can do that using remote screen sharing apps like TeamViewer.
Install TeamViewer host app on the host phone(phone on the stand in this case). Log in to your teamviewer account and setup unattended access to the host. In this way there is no need to tap on the screen to allow access.Install Teamviewer app on the other phone.
Type the code from quicksupport app in TeamViewer app, you will get the display of that camera in another phone.. Now simply click the shutter button to click pics and record videos

Hope this helps
Enjoy!

This won't allow me to open the remote at any time, without also having to click something on the screen of the phone that is taking the shots;). I want to be able to just have the camera sit there for years on end.

@JasonHunter edited, please check


text:
Firefox Android Clearing download history without deleting the file
On the desktop version of Firefox, when I open "Show All Downloads" and there "Clear Downloads", the history of downloads is cleared, but the downloaded files are present in the folder still. This is the desired behavior.
However, on Android Firefox, if I open Tools->Downloads, I only get the option "Delete All Downloads" and when I press it, the list gets cleared, along with the files from the folder. How do I avoid this and get the behavior similar to that in the desktop? Basically, I wish to clear Firefox download history in Android without deleting/renaming the downloaded files.

Doesn't clear search & browser history not clear?

@beeshyams It does clear the download history, but it also deletes all the files in the list from the folder.

In Menu->Tools->Downloads

Maybe you can use an app like folder sync to sync your downloads on schedule /demand, if you don't get Firefox based solution

I would prefer a solution within Firefox. Or that the developers fix this. However, until then, I might have to fall back to FolderSync.


text:
What was my phone doing and why?
I have a Samsung Galaxy S7. Yesterday and today it behaved very strangely. In the order I noticed things:

it thought it was Thursday on Wednesday. I got reminders about appointments that had "already started", that sort of thing. I restarted and it now agreed it was Wednesday
mail stopped coming in. (I use Outlook.) I didn't notice for some time, but looking at what mails I actually got that day, this was the next thing to happen
mail stopped going out. I forwarded some emails to someone else who didn't get them
when I typed a text, I could see the words I was typing, but they disappeared when I pressed Send and were not visible in the conversation. The recipient got the texts.
when I received a text, I got the expected noise and could see the text contents in the notification at the top of the screen, but if I tapped it, the conversation did not update
A hard power down fixed nothing

Throughout this, it worked fine as a phone (voice calls) and both Skype and WhatsApp worked perfectly. There is no doubt that I had data all the time. A game I play while waiting which insists on being connected worked fine, except for the first time when I came home and got on the wifi, where it would neither connect nor object that it couldn't connect. That's when I did the hard power down, left it 10 minutes, and powered it up again.
In the morning I sent a text and to my great surprise, what I typed stayed on the screen and I saw the reply too. However sending me pictures still did not work. Several hours later, emails started coming in and an hour or two after that the person I forwarded the emails to got them. And four or so hours after that, pictures in texts (multimedia messages) are happy to download and display.
Is there a single thing that can be wrong with a phone (and remember, it's not "you don't have data") that could cause this constellation of strange behaviours and magical self fixing?
There is plenty of storage space:

you should reboot your device more often

since reboots, both hard and soft, did not fix this, and the problems resolved without a reboot, what makes you suggest this, and how often do you think I reboot it now, @alecxs?

the issue is lack of memory, too much apps running in background. on my old samsung sometimes the keyboard didn't even print what i type. reboot once a day seems to be the best solution


text:
termux: running termux via adb without *any* direct interaction with the device?
I know how to open the termux app, run (for example) sv up sshd, and then interact with the Android device via ssh, rsync, etc. This is just an example, and the same is also true for any other termux initiated procedures.
However, to do this, it's necessary to perform that manual open and manual sv up sshd command in termux on the device itself.
I want to be able to perform that initial termux interaction from my desktop computer via adb without any direct interaction with the device itself, aside from plugging in the USB cable.
I have looked for solutions, but it seems like no one has come up with any way to interact with termux except by first actually manually opening that app on the device, which I do not want to do.
However, could I have overlooked something? I'm hoping that I indeed missed something, and that somehow I can start termux-initiated procedures via adb.
Does anyone know how that might be done?
Thank you in advance.

ADB shell is just an app (with UID 2000). And apps cannot access other apps' directories without root access. Related: How to run a program in an app context with Magisk?. // You can add sshd to .bashrc or .profile (so that it's started whenever Termux is launched) and then launch the app using adb shell am start -n com.termux/.HomeActivity.

I have root, but even so, I see from the related article that I would have to run a complicated procedure to get the described functionality. However, using .profile and the am start command are doing what I want, so that's good enough for me, for now. Some day I will try to encapsulate that other multi-step procedure into some sort of utility, however, because programmatically running termux-based commands would be quite useful. Thank you!

You can use run-as to access your Termux environment from adb without root or ssh.
Run adb shell and then:
run-as com.termux files/usr/bin/bash -lic 'export PATH=/data/data/com.termux/files/usr/bin:$PATH; export LD_PRELOAD=/data/data/com.termux/files/usr/lib/libtermux-exec.so; bash -i'

This will give you a Termux shell.

Aha! This is what I've been looking for and hoping for during all this time. I want an interactive termux shell that I can use from my desktop computer, and which provides this exact functionality. Thank you!

... and I can even do the following: (1) put that command into a file called /sdcard/termux-shell.sh; (2) run the following from my desktop computer: adb shell exec /system/bin/sh /sdcard/termux-shell.sh

This fails for me with the error: run-as: package not debuggable: com.termux  My understanding from this message that Termux is not set as debuggable and would require recompiling with a flag set to true which isn't possible for me.

@Michael: You may need the latest APK release, v0.118.0.  The version on the Play store has long been deprecated and should not be used.  Unclear whether the version distributed on F-Droid is debuggable, check by running echo $TERMUX_IS_DEBUGGABLE_BUILD, which will be 1 if your version of Termux is a debuggable build.

Per the comment by Irfan Latif above, the following works:

Launch termux

Do the following:
echo 'sv up sshd
sshd started' > .profile

Run this whenever I want to start sshd via adb:
adb shell am start -n com.termux/.HomeActivity

Thank you! This suggestion works, but it configures termux to always start up sshd, even if I am running it interactively via the Android device. I want to be able to run termux interactively both via the Android device and via an external adb connection.

adb shell am start -n com.termux/.HomeActivity
adb shell input text "your command here"
adb shell input keyevent ENTER

Yes, that works, but it only runs one command at a time. I've been looing for a way to remotely run an interactive termux shell, where I type in commands and they each get executed one by one, just like what happens after I invoke "adb shell". The answer by @josh3736 accomplishes this.

this doesn't seem to work if the screen is off on the device

2024 proper solution
Termux allows you to start the run command service through am allowing you to pass extras as well
adb shell /system/bin/am startservice --user 0 -n com.termux/com.termux.app.RunCommandService \
-a com.termux.RUN_COMMAND \
--es com.termux.RUN_COMMAND_PATH '/data/data/com.termux/files/usr/bin/sleep' \
--esa com.termux.RUN_COMMAND_ARGUMENTS '10' \
--es com.termux.RUN_COMMAND_WORKDIR '/data/data/com.termux/files/home' \
--ez com.termux.RUN_COMMAND_BACKGROUND 'true' \
--es com.termux.RUN_COMMAND_SESSION_ACTION '0'

In this command notice how I set the background option to true which is important so that it automatically runs in the background(the notification will show you that a task is being run in the background)
In the example above, we are executing the sleep command and passing in 10 as an argument which will make termux basically execute sleep 10
Once the execution is completed, termux will automatically exit
More information can be found here
https://github.com/termux/termux-app/wiki/RUN_COMMAND-Intent#basic-examples
[Message to mod who deleted my previous post(how do I contact you?)]

This didn't work for me. I got:
Starting service: Intent { act=com.termux.RUN_COMMAND cmp=com.termux/.app.RunCommandService (has extras) }.
Error: Requires permission com.termux.permission.RUN_COMMAND I guess this works only on a rooted phone (mine isn't)


text:
Can I access both cameras, wide and normal at the same time?
Some smartphones have two cameras, working together as one implementing different parts of the zoom range.
Is it possible to use both of them at the same time?
With both at the same time, I do not necessarily mean reading the frames at the same time synchronously, reading both with 30 Hz from different threads would be great.
A problem could be if a camera needs to be initialized somehow, and only one can be in the active state at a time.

Seems possible on some Samsung phones if you are into developing

While we might answer the technical side from the end-users perspective, take note that app development is off-topic since Android Enthusiasts focuses on end-users or power-users (but not necessarily developers) solving their issues.


text:
Can a blocked contact see any number changes?
I would like to ask, whether a blocked contact will receive an information,if I change my Viber phone number?
Is it possible to make the change by only informing a selected group of contacts or everyone I had previous communication with, will get the notification of me changing the number?
Thanks

They will not notice it unless they try to make contact with you after it is done. But things can become awkward if you are both a part of the same group chat. You won’t see their messages but they will see yours. And as a rule, if they are blocked, they won't see any changes of yours.


text:
How do we know when an android version is going phase out and not maintain anymore in the near future?
From the security bulletin I can know that which version of Android is not being supported by Android anymore.
For example I can tell that Android version 7.1.1 and 7.2.1 are not being supported around 4th Nov 2019, by referring to the 4th Nov 2019 bulletin.

Questions:
1) Are there any ways to get the precise dates when Android 7.1.1 or 7.2.1 are deprecated?
2) Or are there any official announcement to get the date for Android 8.0 or 8.1 being deprecated beforehand? So we can plan accordingly to stop supporting that version for security reasons.
3) In wikipedia, old versions means it's unmaintained. But how to get this information from the official docs?

The Android version is not being phased out, nearly 20% of users are on 7.x and they work, so do apps, including newly released apps that must work with 5.x (min sdk level) //Only security patches aren't provided any more for 7.x as you highlighted

isn't a version always deprecated with each new version? imho the precise date is date of new release

@beeshyams: Only security patches aren't provided any more - that is IMHO the common definition of a phased out OS. Just compare it with Windows XP which support has officially been dropped. That app developers still support older Android levels is something that is independent of the OS itself.

@Robert My take is different (without comparing with desktop OS, which is not an even comparison) - if newly released apps can't run on that then it is phased out (for now below 5.x). That's the time smartphone becomes a basic phone. Aside, I am not aware, if there is, a standard definition of what is phased out. One could argue that all earlier versions are phased out when a new version is released. I think what constitutes phased out is a good question to be asked and answered


text:
How to permanently enable ADB in Huawei devices?
I bought a huawei p30 for development purposes. So the first thing i did, it is enable development mode, enable adb over usb, then type adb devices... nothing!
When I enable adb over usb, the setting is not saved! If I go back, and then enter the developer menu, it's disabled again!
I found this workaround:

Dial *#*#2846579#*#*
Select background
Select USB mode
Select "Google mode"
Open settings
Find development options
Enable ADB over USB.

Now it works... for a little while! Just unplug the cable for 1 second, and I need to repeat all the steps again! ADB disabled, USB mode reverted to "huawei mode", and so on! This is ridiculous! I bought this device for development purposes, it should have a permanent way to enable adb, as expected in each single Android device since version 1.0. How devs can debug huawei devices if each time enabling adb is such an hassle???
I must be missing something, how to permanently enable adb on (newest?) Huawei devices?

There are apps in PlayStore that can directly open Development Option page. Not sure if they work on your device but worth a try as this would reduce the number of necessary steps. Another option would be not to disconnect the device from USB.

I was using Huawei mate 10 lite, as I remember I had fixed this issue by selecting Allow ADB debugging in charge only mode at developer options section

It works! Thanks! I did not imagine that it was somewhat related

me too :) you are welcome


text:
Samsung Chat Service Privacy
I'm trying to find out privacy settings behind the wifi chat offered by... Samsung? Its built into my S10e as an additional chat service with little to no information about it. It's free and enables chat over WiFi and to groups of users who have the feature enabled. It also enables Android users to see when others who have the service are typing like on the iPhone.
My concern is privacy. If it's free, how do I know that I'm not the product here?
The Stack Exchange app won't let me upload a 256KiB image so I've added a URL for the screenshot: screenshot of new messages feature

If this app available of non-Samsung phones? If it is listed in Google PlayStore please edit your question and include a link to this app.

This is a pre-installed application, not from Google Play. It is apart of the default messages app used for SMS texting. Very curious...


text:
Asus zenfone 6 E:failed to mount/ cache
Phone stucks on boot loading.
wipe data/factory reset  gives
E:failed to mount/ cache error
wipe cache partition
also fails.
abd sideload also give
E:failed to mount/ cache
Can't open vs..
Many same post suggest TWRP but i don't have it. Did not understand how to install it on a phone can't open.
Many more says EMMC chip is dead. I hope it is not. I know it is very likely but i want to try other options first if i can.

fastboot flashing get_unlock_ability

My old platform-tools fastboot did not have that command.
İnstalled yours, phone says "Result:FAIL (unknown command)".
My phone is from 2015

with locked bootloader you can only try to flash cache.img from EDL mode (Qualcomm) or from Intel Flash Tool (Intel Atom) https://forum.xda-developers.com/showthread.php?t=2839984

I think EMMC chip is dead. only fastboot commands working.
Sometimes you need to accept inevitable.

I can't accept my answer sorry about that.

You can accept after 48 hours!


text:
`adb pull` says it pulled all of the files from my Android phone into my Windows PC, but in reality it didn't
So I am using adb to copy all of my Android files to my Windows PC with this command: adb pull -a /mnt/sdcard C:\backup
And when it's done it says all x amount of files have been pulled, I can confirm that the number of pulled files matches the amount of files that reside inside the folder of my Android storage but when I check how many files are actually in the C:\backup folder, I see about 200 missing or in other words adb skipped about 200 files and did not copy them over to my C:\backup folder.
I understand that this could be due to path limit or due to some files containing characters in their filenames that Windows' NTFS file system just doesn't allow.
How can I see what files are actually being skipped? Is there a switch in adb or some trick?

You can instead use tar on device to create a tar archive with all files and stream that to your PC. May be tar works more reliable: https://android.stackexchange.com/a/194854/2241 If you device is not rooted remove the su part and adapt the path.

@Robert I used adb exec-out 'tar c /storage/emulated/0/123.txt' > 123.tar but it just creates a corrupted tar archive.

@alecxs /mnt/sdcard/ is internal storage and it is also the same as /storage/emulated/0 and no, I am not trying to pull things from a MicroSD, I am trying to pull all the files in the internal storage's root directory.

The tar archive was corrupted (what type of corruption)? May be you are facing a totally different problem with a broken USB cable and/or port. What adb version do you use the latest from Android SDK?

@Robert No matter what file or how many files I add to the tar archive with that command it always outputs a 90 byte archive that 7z can't open because it says "Is not archive". I am using the latest adb, I literally downloaded it today. Tried multiple USB cables, same issue.

Seems like tar has some problems with the absolute path (it then outputs some text which destroys the archive) also you used the wrong quotes. This works: adb exec-out "cd /sdcard && tar c *" > sdcard.tar

* does not match all file names use . instead

Just pulling all files via adb to a Windows computer has multiple problems:

Android/Linux allows multiple files in one directory that just differ in their case.
The file system on Linux allows characters in file and directory names that are disallowed on Windows.
Some file names are completely disallowed on Windows which are just regular file names on Linux/Android.
There is a path limit as you have already mentioned that may cause trouble.

Hence, the best solution to create a full backup of the SD card is to pack all files into one tar archive as all file system limitations of Windows can be bypassed using this method.
Via adb, you create a full backup of the SD card using the following command:
adb exec-out "cd /storage/emulated/0 && tar c * -" > sdcard.tar

This command creates the tar archive on the device and directly streams the data of the tar archive through adb to your PC and saves it there as sdcard.tar.
WARNING: The created file sdcard.tar will be corrupt if tar prints any warning or error message to stdout (this will be invisible to the user executing the command). Therefore, it is crucial to perform an integrity check on the created tar file if the tar structures and the contained files are correct. For more details, see this answer to ADB pull stops after first error.

@alexs You are correct 1 is not possible but 2 and 3 are valid. Filenames with backslash are possible and reserved names like aux and com1 are also possible just as an example.

oh no how stupid from sdcardfs. thought behavior is same as vfat

I wish this worked, but I simply get a corrupted tar archive no matter what.

@computationalprince But the tar size should be correct, yes? Use an hex editor to check if the file starts with an error message.

@Robert I just noticed that tar doesn't exist in /system/bin folder but I have tar installed in Termux but I can't execute it in adb because I don't have permission.

@computationalprince An Android without tar installed, ok that explains a lot. What device do you use (manufacturer, model and Android version)? In termux you should be able to copy busybox/tar to /data/local or /data/local/tmp. From there you can execute it from adb.

@Robert My phone is a Huawei G8 with Android 5.1.1 and I don't have permission on /data/local nor /data/local/tmp althought I can cd into both of them.

@computationalprince Right, access to that folders is only possible via adb. Hence if you really want a warking tar you have to copy the busybox binary to sdcard in Termux. Them in adb copy it from sdcard to /data/local/tmp and restore the executable flag via chmod. Then you can execute tar via /data/local/tmp/busybox tar.

@Robert You were right! I did everything you said and now when I run your command with the new tar path e.g. adb exec-out "cd /storage/emulated/0 && /data/local/tmp/busybox tar c * -" > sdcard.tar I get a healthy tar archive with all the files. Thank you a lot!


text:
Add URL to homescreen
Can I somehow place a link to an URL to the homescreen without having to open it first?
I would like to place a threema:// URL to the launcher -- of course, my browser won't show it long enough for me to choose any "Create shortcut" option, since it instantly opens Threema.

For anyone searching: Fennec Fdroid can do that with a little detour. Create a bookmark for any page and then edit that bookmark -- you can then enter any URL you like. For the bookmark, you can create a shortcut on the launcher afterwards.


text:
Digital Wellbeing in Secure folder Android 10
How can I use Digital Wellbeing in Secure folder Android 10? I am using Samsung A70.
Basically I would like to restrict usage of certain apps inside my secure folder and if possible I would like to have a launcher for secure folder like Desert Island - A Digital Wellbeing Experiment - Apps on Google Play. I am able to install it but I have  to manually activate it everytime I go inside secure folder.


text:
Will this Remove a Permission from an App?
So I downloaded an app from the web today, but it had some permissions I was uncomfortable with granting. So, I used APKTool to decompile the APK, removed the suspicious permission from the manifest, and recompiled + resigned the APK. Then, I downloaded the modified APK on my phone.
Does this approach work? My understanding is that now the app will crash if it tries to do something requiring that permission.

*PS: The reason I did this was because the permission to remove (CHANGE_WIFI_MULTICAST_STATE) did not show under settings/app Permissions of my phone. It only showed up under "All Permissions," where I couldn't simply disable it.

It may work if the APK is not protected against repackaging and as long as you don't execute the function that makes use of the permission. If you do the app may crash or ignore the error just as the developer implemented it.

@Robert my question is, how can the developer ignore that error? If the permission no longer exists, and the app tries using it, shouldn't it always crash?

Android apps are usually programmed in Java and Java allows to encapsulate code in try-catch blocks that allow to catch all errors. The problem is that if the programmer does not expect an error such a try-catch block is often not used. Hence it depends if the programmer was programming very carefully or not.

It will surely remove the permission, but the moment code inside the program executes a function that requires that permission, the app will crash as a result.


text:
How to log errors when using adb pull?
I am using the latest version of adb with the pull command to backup my data.
Sometimes adb pull doesn't backup all of my files, so I am trying to figure out which files have not been backed up.
Using adb logcat -f logcat.txt bugreport pull "my path" "my path 2" just throws me a create bugreport fail! and create bugreports dir error!!. I've tried multiple directories with full permission but with no luck.

What are you trying to do? The presented command is a mixture of two ADB commands which AFAIK does not work. Execute them individually each in one console.

try adb-sync or Adebar

If you want to execute an adb pull comand and at the same time monitor the on-device log via adb logcat you can do so by executing each command individually in it's own terminal/cmd.exe instance.
adb is not limited to a single connection (as the MTP protocol is). Hence you can execute two or more adb command simultaneously. Even multiple adb push or pull commands can be executed at the same time.
However I doubt that doing so will get you much insight regarding your problem with adb pull that some files are not copied via adb pull. The main problem is that adb logcat just displays the log of your device. All errors on adb level, for example if a file could not created on your PC or transmission problems between device and PC are not covered by this log as the device does not know about them.
Additionally I am not sure that the on-device adb daemon writes messages to the logcat log at all.

I wasn't aware of logcat and pull being two different commands. My bad.

@computationalprince adb can be seen as some sort of ssh connection that connects to the device and executes commands commands on-device (e.g. logcat is simply a binary that is executed on-device). Only in case of file transmissions some additional logic (pull/push/install) for the file transfer is executed by adb itself.


text:
How to grant certain apps root permission through ADB?
I have an Android TV box (4.4.2, armv7), and I can login the device as root by ADB (local network). What I want to do is to give certain apps root permission. How can I do it?

You don't give certain apps root permission, but certain apps ask for root permission by executing su binary. It's the developer of the app who decides if the app would perform some tasks with root privileges or not. In order to let apps request root privileges, you need to root your device using e.g. Magisk, SuperSU etc. (whatever works on your device).
When you get root privileges on adb (e.g. by executing adb root or adb shell su) it runs adbd process on device as root (UID 0) user. So all commands which you run through adb have root privileges. To grant root access to apps you need a special su binary which is not shipped with Android.
The usual su binary (like on any UNIX-like OS) makes a transition to UID 0 by making setuid syscall to kernel. This is not possible on Android due to certain restrictions. The special su binary (the one provided by rooting solutions like Magisk) connects to a background daemon to get a root shell for the requesting app, where the app can execute commands with root privileges. However the app itself is still running with its own UID (assigned at the time of installation).
For more details see:

What special privileges “/system/xbin/su” does have w.r.t. root access?
How Magisk works?
How to manually root a phone?

Thanks for ans, and I found there is a file named su which's location is /system/xbin and I run chmod 777 to this file. Then I install supersu on the box but it remind "su binary occupied". So do I have a solution to solve it?

@punnpkin you need to root your device, using e.g. Magisk or SuperSU. The su binary already provided in Android cannot be used with SuperSU. They provide their own su binaries. That's what I tried to explain in the answer. For more details see linked answers.

OK, I learned it, Actually, I'm just looking for a way to root my device without changing the rom. (Because it has some customized content.)

I don't understand this answer. If you can adb root and you run have root privs, why can't you run the app? That doesn't make sense, you grant root access to anything root runs. Why can't someone with root access run an android app?

@EvanCarroll because Android apps cannot make use of SUID bit. Please read “How Android restricts root access?” in the linked answers.


text:
Is the CPU of Samsung Galaxy A10s 64 bit or 32 bit?
I really wanted to know the CPU word length of Samsung Galaxy A10s, running Android Pie. In the first appearance it looks like it has a 64 bit processor, since, it uses the MediaTek Helios P22 chipset, but I dont think apps/programs running in user space have access to 64 bit instructions etc. . Even __aarch64__ is undefined. The OS identifies it as ARM 7 and hence it cannot use AES instruction sets and other features. If it were the ARM Cortex A53 mentioned by MediaTek Helios P22 it should have an ARM architecture of 8.

Is this because the Kernel is 32 bit ?
Or is the Android permissions blocking it ?
How can I identify my Kernel is a 32 bit or 64 bit ?

Please do correct me, if I am wrong !?
Every help will be greatly appreciated!

I can not find the source but I think Android have dropped 32 bit kernel support entirely so the kernel is most likely aarch64. Sometimes vendors only ship 32 bit userspace on low end devices, to save memory.

Related: Could a 64-bit hardware device run a 32-bit Android version?

As suspected by OP, the hardware is 64 bit but it is running in 32 bit mode as mentioned in this reddit which in turn refers to geek bench for proof.
Apps like AIDA 64 can reveal this

Source
Also Antutu, if you have it installed, as it is removed from Play Store
As general info, see How to find ARM processor version on android device?

I wonder why they would do this on a 64-bit-capable processor...

@NonnyMoose - Samsung cannot sell Exynos (Samsung developed) processor phones in USA (legal reasons ). They have to use Qualcomm in USA. That means 2 models of phone with same OS. This has been a sore point with users, Qualcomm often scoring better. I am guessing that price differential between 64 bit processors (Qualcomm Vs Exynos) is more than 32 bit, so to keep the cost comparable in both markets, they ended up using 32 bit. Or one of the 64 bit processors wasn't ready to be used. Better to have both models underutilized rather than cause more dissatisfaction, a business decision –

@NonnyMoose Memory. Shipping with both 64 bit and 32 bit userspaces costs a few hundred MBs of memory. With all services up and running a 2GB device may have 800MB left on a good day. Not many 3GB and very few 2GB devices ships with 64 bit userspace.

@user3528438 I wonder if all of the userspace code is 64-bit. In near past there were issues with some core native services (e.g. audioserver, you may find reference in my comment to the question) and they were always 32-bit even on fully 64-bit ROMs.

@IrfanLatif I think 64 bit systems ships a full 32 bit environment as well (hence the memory overhead), because some apps releases a 32 bit only version, but google is trying to change this by forcing everyone to release a 64 bit version of their apps.


text:
WhatsApp Built in Scanner Won't Work
I have spent 2 days reading everything on the web concerning this issue and trying all the solutions suggested, with no success.
The problem:
When I try to connect to to WhatsApp Web, the QR will show on the screen, but the phone will not read it. It seems its not even trying to read it, because I don't see the process line I used to see running up and down the scanner (though I have re-installed WhatsApp, so maybe the new version simply does not have that line, I don't know).
Relevant Information:
I am using Chrome, and my phone is a Samsung Galaxy S7 with Android 8.0.0.
I have been using Whatsapp Web successfully for nearly a year with the same laptop, same browser, same phone. Once in every 2-3 months I get disconnecte/logged out from the web version, so I set it up again (the usual way, reading the QR code and everything) without any problem, so its not like I am holding it wrong or something like that. I got disconnected again 2 days ago and cant set it up since.
The problem started after I made some changes to my Chrome Browser (removed many extensions and add-ons. and added others).
Here's what I checked/tried so far:

My internet connection is fine and the speed is normal for both phone and laptop.
The QR code and phone camera are fine - I had no problem reading the QR code with 3rd party scanners (not the one within whatsapp).
I cleared cookies and browsing data on Chrome. I ran Chrome in Incognito mode.
I installed Edge and Tried with that browser - It didn't work.
I rebooted both laptop and phone.
I un-installed and re-installed whatsapp on my phone .
I've checked whether there are any updates to my phone software. There are none. It is up to date.
I ran Avast on my PC, and than installed Restoro and ran it too - with no impact.
I made the QR code larger to 175% as some suggested (though I didnt expect it to work because like I said, I've done it many times before without having to enlarge the QR).
My phone screen is not too small, I see the "OK, got it" button. Like I said, using the same phone I used before without any problems.
I thought maybe there is a conflict between the 3rd party QR scanner (which I downloaded recently) and the one within whatsapp, so I un-installed the 3rd party = didnt help.
I turned off wifi on the phone to use the cellular network. turned it on again. switched plane mode on and off again - did not work.
(Added) Cleared the cache of the camera app - no impact.

I do not wish to use an Android emulator on my laptop, which I understand is a workaround.
I really love Whatsapp web, hate to type on the phone. I am just about to give up.
Anyone? Anything? i will be forever in your debt :)
Thanks,
Galia.

Seems like you really covered all the bases. Cant think of anything you didn't try yet. Just wanted to let you know that as you suspected, the line going up and down when looking for the qr code, is not there anymore, so it's not just by you

Really? That's interesting, tnx/

Found a decent workaround: I managed to scan the native app in Windows, installed from the link whatsapp.com/download. It's not a perfect solution, because I rather have it as a tab on my chrome, rather than a stand alone application, but it's close enough. I wish Whatsapp will come up with another authentication method, because it seems that many users are experiencing problems with the current approach.

If you use Firefox, you could try this add-on


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Why i am not able to open my archieved chats?
My archieved whatsApp messages not opening at all. I am not able to click it and open it(convert)

Sorry I'm failing to understand... Did you export the chats out of WhatsApp?. Because the only option in WhatsApp to archive chat can be found by scrolling to the bottom of the screen and going into the chats hidden. Please clarify which archive method you used so I can help you further

To open WhatsApp archived/exported chat, you need an app that is able to open .txt file, because WhatsApp archived/exported chat has that format. You can use this text viewer app from the Play Store.


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How to modify CSC file of samsung sm-j500fn?
My phone origin is the UK and I am in Sri Lanka now. My phone modemst1, modemst2 were reset and also I forgot to backup.
dd if=/dev/zero of=/dev/block/bootdevice/by-name/modemst1

dd if=/dev/zero of=/dev/block/bootdevice/by-name/modemst2

After reset it has asked to unlock the network.
I've tried many solutions such as flashing stock ROM of UK before I had custom rom(arrow os), zx3 tool pro. I could not do it. I don't plan to buy a code since I think, It can be recovered.
I think it can be done via modifying the CSC file since it is specific to geographical region and carriers and it contains the software packages specific to that region, carrier branding and APN setting but I don't have enough knowledge to modify the CSC file.
Another possible solution may be flashing the living country CSC file but I could not find CSC file only for my j5nlte phone with Sri Lanka.
Can anyone suggest how to modify the CSC file or provide any solutions to unlock the network in my device?
Thanks in advance.........

Does this answer your question? Samsung Firmware Modifying!

@alecxs no ... not working

https://forum.xda-developers.com/showthread.php?t=3762572

If your device is rooted, you can try this app https://play.google.com/store/apps/details?id=org.vndnguyen.phoneinfo

I've tried but my bad luck the app is not working my phone @beeshyams

Sorry to hear that. You can contact the developer on XDA https://forum.xda-developers.com/showthread.php?t=2609045


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Unable to unlock Asus Zenphone 3 bootloader
tried unlocking using official APK as well as the unofficial .
https://forum.xda-developers.com/zenfone-3/how-to/zenfone-3-ze520kl-ze552kl-unofficial-t3738811
https://wiki.lineageos.org/devices/zenfone3/install
I guess bootloader is not unlocked, although it said unlocked. Any other way to unlock the bootloader or troubleshoot the unlock
###############################################################################
#                                                                             #
#                           Device Unlocked                                   #
#                                                                             #
###############################################################################
< waiting for device >

...
(bootloader)    Device tampered: false
(bootloader)    Device unlocked: false
(bootloader)    Device critical unlocked: false
(bootloader)    Charger screen enabled: true
(bootloader)    Display panel:
(bootloader)    Device is_authorized: false
(bootloader)    ssn_num: G9AZCY05W199BPD
(bootloader)    isn_num: N0CY1637MB0028482
(bootloader)    check_fused: 0
(bootloader)    Device resize: false
(bootloader)    BOOT_COUNT : 466
(bootloader)    SB=Y
(bootloader)    Re-partition: false
(bootloader)    Device had been rooted: NO
(bootloader)    Device has copy fsg to fsgCA: false
(bootloader)    Device last copy fsg status: fail
(bootloader)    verity_mode: 1
(bootloader)    is_ffu: false
(bootloader)    verity_counter: 0
(bootloader)    total verity_counter: 0
OKAY [  0.211s]
finished. total time: 0.212s

target reported max download size of 534773760 bytes
sending 'recovery' (21090 KB)...
OKAY [  0.511s]
writing 'recovery'...
FAILED (status read failed (Too many links))
finished. total time: 0.663s

thx for sharing the unlock tutorials. you are right, the message "Device Unlocked" is just a hard-coded text and not actually confirmed unlock status

i tried unlocking a Rog Phone 2 the other day... didnt work either... didnt really try though, ill try again in a few days (i work at a phone repair/resale factory... im quite busy)


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How to enable USB "Audio Source" option on Android 9+?
A lot of screenshots in the Internet mention a 'audio source' USB configuration for Android. For example, this one from Google:

However, I cannot see this option with my SM-A510F with Android 9 (LineageOS 16).
Is there something I can do to enable it? Is it definitively gone from Android?

You do realize that the Samsung SM-A510F is from 2016 and has a headphone jack so it is unlikely to have the drivers for USB Audio. Otherwise you should show what you see on your device.

One choice is MIDI. Thinking to myself, "Well, THAT'S audio...", I gave it a try. My USB DAC (https://reference-audio-analyzer.pro/en/title-report.php?id=1177#gsc.tab=0) is now working again! :D Pretty chuffed! Your mileage may vary, but - it's worth a try! :)))

Android devices can work in USB host or device mode. Host is the one which controls USB communication. PCs mostly operate in host mode. Device is the one which is being powered and controlled by the host. Flash drive is a common example of USB device. Linux/Android kernel supports device mode through different gadget drivers. UMS, MTP, ADB are different gadget modes on Android devices.
Audio over USB in Device Mode
On Android devices, technically it's possible to stream Audio over USB both in host and device mode. Since Android 4.1 the latter mode is “provided by Android Open Accessory (AOA) 2.0 and provides limited audio capability”. It uses the USB Audio Gadget Driver in kernel (built with CONFIG_USB_AUDIO option) and the accessories supporting AOAv2 protocol are built using Accessory Development Kit (ADK).  Custom Accessories page states:

AOA protocol specifies how an accessory can establish communication with an Android device via USB. Due to the low power output of Android devices, AOA requires the accessory to act as a USB host, meaning the connecting accessory must power the bus.

But as per official documentation:

Accessory mode audio has not been widely adopted, and is not currently recommended for new designs.

And the AOA protocol documentation warns:

Caution: AOAv2 audio support has been deprecated in Android 8.0.

It means Android 9+ devices won't be able to function in device mode while streaming audio over USB. So the Audio Source USB configuration option is no more there.
Audio over USB in Host Mode
However Android devices support audio peripherals in host mode (kernel must be built with CONFIG_SND_USB_AUDIO). Since AOA is specific to Android, such accessories aren't usable with other hosts like PCs. So there was a demand from audio peripheral manufacturers, device OEMs and ROM developers community to support standard USB audio out capability in host mode (e.g. see this, this and this). Support for a subset of USB audio class 1 (UAC1) features was added in Android 5.0.
USB Device classes specify the standard protocols for USB peripheral functions so that the host can inter-operate with them without requiring any hardware-specifc driver (i.e. in driverless mode). USB Mass Storage (UMS) is a common example. All Mass Storage Class (MSC) compliant thumb drives work on all OSes including Linux, Android and Windows, irrespective of the device vendor. In the same way the USB audio peripherals which are USB Audio Class 1 compliant work with Android devices like on any other USB hosts e.g. PCs.
So host mode USB audio covers wide range of USB-based peripherals including the headsets that follow the USB headset specification.
When a UAC1 compatible peripheral device (like a DAC) is connected to USB port on Android device, digital audio is automatically routed to that peripheral. However if an app wants to use advanced USB host APIs to interact with the peripheral (and not simply the audio routing) , it's possible to Disable USB audio routing in Developer Options.

bro, can we disable automatic routing to USB audio programmatically? Can you answer this https://stackoverflow.com/questions/77436297/change-audio-source-for-speech-recognition-android

@Qamar your app should have WRITE_SECURE_SETTINGS permission granted. Then call Settings.Secure.putInt(context.getContentResolver(), "usb_audio_automatic_routing_disabled", 1). // No sorry.

@IrfanLatif Hi Irfan. Do you mind taking a look at this somewhat related question I have? Android 13 car head unit won't route phone calls or AV-IN audio to USB DAC/AMP
https://android.stackexchange.com/q/255930/405546?sem=2


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Huawei P8 Lite 2015 soft-bricked and won't turn on or charge
I got a Huawei P8 Lite (ALE-L21) model that I received from someone. The issue was that it kept booting into this recovery mode phase that kept asking to flash software update again showing two errors.
At first, the phone would charge perfectly, and as soon as it could power on, it quickly jumped to the recovery mode. After a few days later, I decided to come back to the phone but unfortunately, it wasn't powering on. Every time I put it on the charger, it just shows red blinking light once, then nothing happens. Sometimes it would blink red and green on the LED light, but still nothing happened.
I have the full stock ROM of the phone on a memory card (SanDisk class 10) and it's been on the phone for some time but still no luck. I tried leaving the phone on PC all night but I didn't respond.
Can anyone tell me what I need to do to get this phone powered up?

Easiest answer
https://huaweiflash.com/how-to-flash-huawei-stock-firmware-all-methods/
Basically = press the right buttons to get into bootloader or flash mode.
HiSuite = easiest.
SDCARD FILE MODE = meh...

SP Flash Tool
is the most difficult - But you essentially leave everything as it is, but select the "scatter file"

That file is in the correct firmware for your phone.

Mediatek SP Flash Tool can not flash HiSilicon Kirin chipset


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Is it possible to uninstall the Google Play Store without affecting Google Play Services?
I have a rooted Samsung Galaxy a50 with a stock ROM installed. However, after using an app (System App Remover) to uninstall Google Play Store (I removed the Google App also) — many apps simply crash on load, and I am familiar with the

App won't run without Google Play services, which are not supported by your device

error. Perhaps I've forgotten something else that might come into play (I rooted this device a while ago) but reading around it seems these apps are somewhat tethered together and the way to separate them is not entirely clear.
I am confused because I still have GmsCore.apk, GoogleServicesFramework.apk (not Phonesky.apk) in /system/priv-app, so I'm unsure as to exactly what the problem might be.
I'm aware that to do this right will almost certainly require a re-flashing my phone, but at this stage I still feel I'm just firing into the dark so if anyone has some light to shed on the right path it would be very much appreciated.
TL;DR:
I want to remove the Google Play Store without affecting apps that rely on Google Play Services. Is this possible/reasonable to achieve with a stock ROM on a rooted phone?

NO. Why? Tap on the Play Store tag you used and see it's tag wiki (click on learn more), repeat on other tag.

Some apps are dependent on google play store links...
They have to be installed separately (or the link must be broken)
My method: install from alt APK source (like aptoide)
you can patch the apps with a good app manager to "break play store link" (thats the command option in said app manager)
However... Some apps yet require license validation.
This requires a patch. "Lucky patcher" is good at this...
And since im sure some disclaimer is needed... Lucky patcher can be used to pirate apps, but serves many functions, and if you own a license to said app... you are not "breaking any rules"

Play Store links like https://play.google.com/store/apps/details?id=com.whatsapp work on a device without Google Play Store installed they just open in web browser as they are valid web links. Of course download is not possible on the GooglePlay web site.

link meaning the app "Checks" with google play when it starts up...
However... that is irrelevant when installing them seperate. an app manager "Breaks that link" meaning, stops it from caring about google play store...

Two additions to the license check: 1. Even free apps can perform a "license check" if they want to download an "APK Extension file" via GooglePlay. 2. Google recommends to perform license checks not in-app on client side but on server side. Lucky Patcher will not work in that situation. See https://developer.android.com/google/play/licensing


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What is the URL of the bookmarks or favorites section in Chrome for Android?
I need to add my bookmarks window to the main page. For that, it asks me for a URL which I don't know what it is. I know that the URL for the history list is chrome://history.
I tried with the PC or desktop's chrome://bookmarks, but it didn't work.
What is the URL of bookmarks or favorites

There is no such URL for Chrome for Android as of version 80.0. All Chrome specific URLs are listed and can be accessed from chrome://chrome-urls. Bookmarks related URL is not listed there.
Second, for a user to access their Bookmarks a separate activity is launched named org.chromium.chrome.browser.bookmarks.BookmarkActivity, but this activity cannot be launched outside of Chrome.
In short, what you are after and specifically in the manner you are after is not possible on Chrome for Android.

If you're trying to set the home page URL, try this one (works fine for me in Android 11 Chrome):
chrome-native://bookmarks/
This will directly open your bookmarks when you launch Chrome (i.e. if there isn't already a tab open).


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"Keep WiFi on during sleep" on Always not working
I have set "Keep WiFi on during sleep" on "always", however it does not seem to work.
The connection keeps established with my router (I can see the wifi icon), however I need to unlock my phone and open WhatsApp before web.whatsapp notices my phone is connected again.
I'm not sure if this is a whatsapp or an android problem, I was hoping someone has the same issue and/or solution.

Have you tried to disable battery optimization for Whatsapp? What device do you use (manufacturer and model)?

Hi Robert, I did not had battery optimalization for whatsapp disabled (I didn't even know you could set it on an app-basis). I have disabled it now. I will report back over a week if the issue still presists or not. (ps, I got a samsung s7)

The changes dont seem to work.


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MicroSD permissions & move applications to microsd
I am using Android version 9.
I was using my mobile with an microSD, formatted as external storage.
Most applications were moved to microsd/running from there.
So I decided to buy a faster one; I copied all files to my PC (just copied all files loosing all extra attributes).
Then I formatted the new one as external storage and I copied all files.
But it crashed (DoA) after a few hours. During troubleshooting I accidentally formatted as internal but didn't work (obviously). Luckily no data was lost as it wasn't writable.
Now I have again a working microSD formatted as external.
I copied all files to it. However, all application are not capable of moving to microsd and use the internal storage.
Any idea how to make "move to sd card" button available again ?
Thank you

If you switch back to the old card is the button usable again? Hence is it a system problem or a problem with the new card?

Unfortunately, the old card was formatted a few minutes before the first card got unreadable.

i doubt you was able to move apps to MicroSD Card as portable storage at any time. format MicroSD Card as adoptable-storage then android will let you move apps (migrate data)

If I format the microsd as internal storage it will not be readable from any another device. But my old microsd was readable and I could see data from apps in there.
Probably android 9 does not support that anymore.


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Recover data from Download/Odin Mode on phone that won't boot into Recovery?
Is there any way to get the data out of a Samsung phone that will boot into Odin Mode / Download Mode but won't boot into Recovery or anything else?

@alecxs Does S7 have EDL mode?  I guess not because mine is Exynos.  This says "The decrypting bootloader capability for Exynos processors enables unlocking, as well as full file system and physical extractions from popular Samsung devices."  Is there something similar I can put on my phone to dump out the internal storage?

This says "Samsung does not use the Qualcomm EDL mode even in its Qualcomm-equipped handsets...Instead, Samsung implemented its own proprietary programming protocol called Odin. Odin can be used to read the (encrypted) content of the device. ...
For many Samsung models, one can use one of the engineering boot images leaked from Samsung or one of its service facilities...These engineering boot images are developed and signed by Samsung proper; they allow full, unrestricted access to the device storage."

you did find a useful site, thx for clarifying

So if this has ENGBOOT for S7 Exynos, then I could burn that to the phone and somehow extract the device storage from it?

members on xda claim it is not a trusted source, and it's not clear it is for exynos, but yes you can flash eng boot + twrp (odin may wipe userdata after flashing, heimdall does not) but the problem remains you probably can't boot any other than download mode. and you can't extract data in download mode, only flash ROMs. can you add picture of download mode screen?

beware the bootloader can't be downgraded, do not flash higher version of bootloader (it is the red digit on this example:  https://mobilefirmware4u.blogspot.com/2018/05/samsung-galaxy-s7-combination-rom-g930f.html) before flashing TWRP (does not support encryption/useless) please read about RMM protection (not sure if this concerns combination firmware)

@alecxs Oh, so if it won't boot into recovery, it won't boot into ENGBOOT either?  It has a "G930F" file inside, which is the Exynos variant that I have.

@alecxs Download screen: https://i.imgur.com/ZsJJ33B.jpg  (I like how the logo is burned into the screen now from sitting that way for weeks...)  :|

please try it is normal boot mode not recovery mode. the question is why it doesn't boot at all, i doubt another boot.img can fix

maybe volume and/or home buttons stuck or short circuit? or there are some broken instructions left on cache partition (failed OTA)? or data partition corrupt (broken encryption)? or empty slot (not sure it's A/B device)? or emmc wear-out?

@alecxs I don't think the buttons are broken.  I don't know about the other issues, they could be responsible.  What is "empty slot"?

you can flash cache.img and see if this fix something (that does not harm). empty slot mean no ROM installed in 2nd slot (should never happen). read more about A/B device (idk if valid for S7)


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Macrodroid -- stop loop when screen touched
Macrodroid question.
I have the following macro, which needs to loop:

UI Interaction
Wait 1 second
UI Interaction
Wait 2 seconds
Macro Run [This Macro]

How can I break the loop between Step 4 and Step 5 (Macro Run), if the screen is tapped, during that 2-second delay?
I have considered creating a second macro, that will terminate the first macro, upon trigger of screen tap, but screen tap is not a UI Interaction option as a trigger for the second macro.

@beeshyams  thank you, I'm not clear on your suggestion. In Dev Options I have Show Touches (show visual feedback when screen is touched) and Show Touch Data (touch data is visible on screen).  I'm not clear how a recording of a touch could be a trigger, though.  I need the trigger (to stop the loop) to be the actual touch I make, on a random place on the screen.

Like I said, it was  just a guess and probably wrong. What I thought was it could be somehow recorded and would work as trigger, which clearly is not the case. Sorry for suggesting without trying it


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Cannot find which alarm to wake me up
I am using oneplus 6 with Android 10 in OxygenOS 10.3.3.
In recent 2 days, I was waked up by the mobile alarm at exactly 08:30 am every morning.
However, I cannot find the alarm app which generate this wake-up alarm.
I have checked the recent app, there is no app running recently at around 08:30.
I search my app with the keyword alarm, I found 2 app.  I am sure that I does not set the wake up time in these 2 app at 08:30.  Actually, I set the wake-up time to 07:10 for one of the 2 app.
So, I feel quite strange.  Where is the 08:30 wake-up time set ?
Is my mobile hacked ?
Can anyone help me to find out why there is an alarm at about 08:30 am ?

Search for "clock" in your apps. Also see if Notifications reveal something

@beeshyams Thanks.  I find a clock app which generate this alarm. I forget that I have set it up.  Very strange, this app does not show up in the recent-app after it ring at 08:30

Well, you may self answer the question

As suggested by @beeshyams, I search my app with the keyboard clock.
Then, I found an app which set the wake-up alarm at 08:30 am.
Very strange, this app does not show in the RECENT APP list after alarm ringing.

Some apps (or to be more specific, activity and task) can request not to appear on the recent app list after closing.


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Can't load operating system
I recently flashed a local build of AOSP to a Pixel 3a XL.  After rebooting and re-locking the bootloader I get the following error:

can't load operating system

Any suggestions to resolve this?
The steps which got me here: I downloaded and installed a factory image for 'bonito', flashed to the Pixel 3a XL, and after rebooting everything works fine.
I then built and flashed AOSP from Build: QQ2A.200501.001.B2 with TAGNAME:  android-10.0.0_r35 via the usual:
choosecombo 1 aosp_bonito user
m

and then:
fastboot flashall -w
The result is the error above.  Any suggestions would be great!

A local build is not signed by Google hence a locked bootloader will refuse to load this operating system.

I wrote in my question that the bootloader is unlocked.

Okay, I implied.  I stated I had "re-locked."


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Android Version differs from expected API level
I have found a pretty old device Huawei Ascend Y210. This mobile officially has Android 2.3.3 (API level 10). I found an online custom lollipop ROM for the specific mobile. The device has CWM as custom recovery. The zip file (the rom file) was installed successfully. The environment feels like android Lollipop should look like. Going to the mobile's settings > About phone > Android version, the version is 5.0.1 as expected. Using the command adb shell getprop ro.build.version.release the result is 5.0.1 indeed. However, I tried running adb shell getprop ro.build.version.sdk the result is 10 which is the API level of the stock android of the phone (Android 2.3.3). Apps made from API level 23 will fail to install as the API level is getting recognized as 10. Changing the apps' Minimum API level to 10 using APK Editor Studio, allows the app to get installed but it crashes once I try to open it.
Is that a bug? I mean can I somewhere change the API level of the device? Or is the ROM a scam and the android is never really getting updated to 5.0.1 and the ROM just changes the graphic interface?  How is it even possible to trick the adb that the android version is 5.0.1 but keep the API level to 10?
P.S.: If someone has any ROM for Huawei Ascend Y210 with android 5.0.1 or higher handy, I would appreciate a download link.
Thanks in advance!

May be the ROM author was only aiming for the look-and-feel of Android 5?

@Robert that can be verified easily: adb backup was introduced with ICS (Android 4.0). If it's indeed only "surface polishing" of a Gingerbread OS, adb backup won't work. If it does work, it's a clear indicator of at least Android 4.0 (or higher) being present, and the ROM dev maybe just forgot to update ro.build.version.sdk in build.prop.

@Izzy I tried running adb backup the result was
adb backup -apk -shared -all -f mybackup.ab
WARNING: adb backup is deprecated and may be removed in a future release
adb: unable to connect for backup: closed
The device is getting recognized when I use adb devices.

@KarampistisDimitrios the warning comes from the adb executable on your computer (unfortunately, it looks like adb backup shall be dropped, leaving non-root users in the dark again). The second one is the interesting one here: it indeed seems the ADB daemon on the device doesn't know about the backup command; as you're unlikely to be on Android 11+, this must mean you're on < 4 then – and the "5.0.1" is fake.

You are a little bit late searching a for a custom ROM. There was a CyanogenMOD release for that device but the download links have long gone dead.

@Robert Yeah I have a CM 10.1 copy but it stuck in bootloop

As Izzy mentioned the issue here was that the owner of the ROM had modified the ro.build.version.sdk in the build.prop without actually provide any feature of the API level 23. I am not sure if Fidz's answer is correct since I could not find any resource online that claims the same thing (correct me if I am wrong), Google's official site claims nothing about the API level, it just mentions some thing about the Android Compatibility regardless of the API level and the hardware. I could not find any ROM for the device since it's pretty old and almost every support for the Huawei and Honor phones on custom ROMs and rooting is dead after Huawei disabling the ability to unlock the bootloader.

Every Android device has its own API level.
it is not a bug, while you use a feature/app that requires higher API level but the device API level is lower than the requirement, the app will surely crash
API level is based on the Android version of the device, but then it also uses the hardware resource, so even if it's upgraded to a newer version of Android, it can't advance the API level higher than the hardware resource available.


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Android File Transfer shows folder ans then pops up the can't access device storage message
android file transfer was working fine until today.
Usb debugging is on.
File transfer is selected on the usb connection.
I am able to see the folders and files but the message pops up and it is not letting me access them and it also works with another androis plugged in to the same mac, it just doesn,t work with my android.
I dont have samsung kies nor samsung smart.
What can i do?

reboot your phone and try again. The files/folders seen via USB connection don't come from the file-system but from the MediaService database. Sometimes this service crash or presents outdated data.

I tried rebooting several times, android file transfer opens up but immediately popa up the can't access device storage message. I meant that the window where all the folder shows comes up but it wont let me do anything since the message pops up and if i click ok, everything closes. In other hand i tried it with a dofferent android phone and it works fine.

maybe physical problem with connector? try mkdir sdcard; adb pull -a /sdcard sdcard

I had to wipe out all data in the cellphone and its working now


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Bluetooth audio as input for video recording
Apps like Bluetooth Mono Router & BTmono let you hear music on old Bluetooth (BT) earphones that were mono (meant for voice calls only since they support Headset Profile (HSP) and don't support A2DP profile) . (Edit : MonoBt play is another such app)
So, if you have such mono sets lying around, you can use them for listening to music, YouTube, etc which is good.
There is a more interesting aspect to it - these allow you to use your BT ear sets  (whether mono or the latest ones supporting BT 5.0 ) to input audio into a video recording on your cell phone. You can comfortably record videos with your BT audio input as long as you are in range, without using wired microphone or UHF transmission. See Bluetooth input for video recording : Android 10, One Plus 7
How does this work?. (I've spent several hours unsuccessfully searching the net and sister SE sites) .

I requested developer Bluetooth Mono Router to explain this and if possible answer the question here but there is no response. What I could gather from comments and reviews is this :

App creates a virtual call environment thereby letting audio (music etc) be treated as voice and hence you can hear using mono ear sets meant for voice calls.
Recording of audio is not  by design. It's an incidental artifact of the virtual call feature. It's not a design feature.
This has nothing to do with Bluetooth versions


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Google Chrome and picture reenabling and reinstalling without authorization or interaction?
As somebody really wary of Google in general, the first thing I did on my phone was to disable Chrome and Google Pictures, and replaced them by apps from F-Droid
For a few days now, I've seen them reappear in my app drawer, and with careful observation, the play store seems to be re-enabling and reinstalling them by itself when checking if updates are available.
Uninstalling and disabling them again just kick the can down to the next repository upgrade.
This question talk about google chrome, but do not give an explanation for google pictures.
Auto updates are disabled, android 9.

Known bug and the link in the answer makes it even more scary

This was a problem I noticed after updating my OnePlus 6 to Android 10. I didn't get the time to investigate the logs when my Play Store, YouTube, Photos, Play Services and GSF kept re-enabling themselves. One thing I realized was that  if I used a third-party app to disable them they got re-enabled after a while. But if I disabled them using Settings app, they never got re-enabled. This is what I suggest for you.
Also, I keep them blacklisted in my firewall, just to ensure they don't connect to internet even if they manage to re-enable themselves.

I actually disabled them with Settings on the first time, lets hope /e/ comes to my device soon so I can can it alltogether...


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Best way to back up home screen layout on Android?
I have a Motorola Android phone in which I have around 400 apps that I have put into folders and carefully chosen a layout which has taken me a long time. I want a way to back up this layout and Motorola doesn't offer a this service (which other major phone manufacturers do). I know this can be done by using Nova Launcher and other launchers which have back up options but this means I have to recreate my layout again in Nova Launcher as it can't import my current layout from the Motorola Launcher which will take a long time.
Is there a way to at least dump all the current apps I own into Nova Launcher? Does anyone have any other ideas (other than getting a new phone)?

make some screenshots as backup

Arrangement of apps whether on home screen or in app drawer is part of app data of launcher app. If your launcher app doesn't offer support for Import/Export of user settings, than try using adb to backup your launcher app's data. Verify the backup and see whether the user settings were indeed backed up not.
If adb solution is not useful than the only way is to get the device rooted and use a root based backup solution, such as by directly copying user settings from launcher app's data directory, or by using an app based backup solution such as Titanium Backup app.
Note: in all likelihood rooting the device would destroy all of your data.