text:
Why can't I browse to my desktop using its .local hostname?
I have a PC whose name is "mypc". It's accessible on the local network.
https://mypc.local correctly displays its website when browsed from Mac, iOS, and itself.
However, using my Pixel 3 with Android 11, browsing to https://mypc.local says “This site can’t be reached”. ERR_NAME_NOT_RESOLVED.
Interestingly, if I remove the ".local" and try browsing just to https://mypc, the browser finds the host correctly. It says "Your connection is not private" and ERR_CERT_AUTHORITY_INVALID (which just means my self-signed certificate isn't configured to expect "mypc" because it expects "mypc.local").
I've tried Brave Private, DuckDuckGo, and Chrome.
How can I fix my Android devices to correctly use the .local hostname?
P.S. I've seen the following questions, but those answers don't apply to my case since my network router is correctly mapping mypc.local to the specific IP of that PC. Additionally, even Android is aware of how to resolve "mypc" to the correct IP, so I'm curious how to get it to treat "mypc.local" the same way.

Accessing local computer using hostname
How to ping a local network host by hostname?

P.P.S. I also just tried from an old Nexus 7 with Android 5.1.1. The results are basically the same as with Android 11. https://mypc.local/ does not work and says DNS_PROBE_FINISHED_NXDOMAIN. https://mypc finds the host correctly but says NET:ERR_CERT_AUTHORITY_INVALID.

Check the "secure DNS setting". If it is activated your local DNS server (e.g. in the router providing the .local addresses) will be ignored and instead a secure connection to a DNS server by e.g. Google is used. Of course this DNS server knows nothing about your local devices.

@Robert My router is the AT&T gateway Arris BGW210-700, which does not seem to have any DNS settings in the config or even mentioned in the PDF of its manual. Are you saying there is a "secure DNS setting" within Android 11? I searched but couldn't find it. Thanks for your help.

Most routers have a built-in DNS proxy that performs the resolution of .local addresses.  I just checked and it seems like the secure DNS setting is called Private DNS.

@Robert I'd changed Private DNS on my Android to one.one.one.one (https://1.1.1.1/). But even though I just switched it back to Automatic, I'm getting the same results as my question above.

You need to disable private DNS (Off), otherwise your router DNS is not used and you can not resolve .local addresses.

@Robert I switched Private DNS to Off and then enabled Airplane Mode for a moment (since I think sometimes that's necessary), but I'm getting the same results as my question above. I appreciate your ideas! They seemed like reasonable steps to try.

May help with Search Domain (.local in your case) issues: https://android.stackexchange.com/a/220129/218526

@IrfanLatif I appreciate the link. I've studied your post multiple times (and others by you), but I'm confused about what I can do to solve my problem. Toggling to Airplane Mode and back off hasn't worked. Waiting 48+ hours hasn't worked (to let whatever cache expire). Restarting the phone hasn't worked. It's bizarre to me that iOS, Mac, and Windows all resolve mypc.local but Android 11 so far does not. Thanks for any thoughts. From your posts, you seem like you're exactly the type of person I was hoping would see my post! Thanks.

Any thoughts, @IrfanLatif? Thanks for your help.

@Ryan I can't be very specific in your situation. Your question is more about troubleshooting than a precise answer. Make sure your DNS traffic isn't encrypted. Secondly force it to go to your router by using iptables (if rooted) or VPN. Then use dig on Termux to see what response your DNS query gets back. This should certainly lead you to some conclusion. You can follow any DNS troubleshooting guide. Android-specfic things are explained in my previous answers on the subject.

@IrfanLatif Ok, thanks for the hints.

I think https://issuetracker.google.com/issues/140786115 (https://bugs.chromium.org/p/chromium/issues/detail?id=405925) might be the problem.

@Ryan - Yes. That's the one.

Looks like Android has supported .local mDNS since December 2021 through Google Play System November 2021 update. Ref: Esper.io, Android Police

@AndrewT. Thanks for the update!


text:
What apps are prevented from Amazon Fire tablet?
I am thinking of getting an Amazon Fire tablet HD 8. However, I have heard that Amazon restricts the apps that can be installed on it. Is this the case? Or is it just the Google Play store is not available? Because, I've also read that because it's Android-based, it is possible to install Google Play Store.
Can APKs be downloaded/installed from other sources? Specifically, I need to know if particular apps are available on it (FlipAClip, Soundtrap) as not having these would be a deal breaker.

It's Android, so most apps should work by sideloading. The only way to know if the app is incompatible is by physically testing the apps on the device. If they turn out not to work, you can simply flash a custom ROM and problem solved.

"simply flash a custom rom" - HaHa ROTFL, this man has humour! :)

source: Stack Exchange

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

sort: votes


text:
Are non indian sims work in this mobile?
I recently my Indian fb friend bought a Samsung F41 mobile online. On the package seal, it's written "Indian SIM Cards only".
Are non indian sims work in this mobile?

The restriction only affect users the first time they activate the phone. In short, just for the first time you'll have to use an Indian sim and afterwards you can use any sim card from any part of the world.
Source - Samsung: We don’t region-lock our phones (apart from when you first activate them)

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


text:
Factory reset not improving performance
I've been having some problems with my Razer Phone 2, running Pie.  I wasn't getting MMS messages from some people.  I tried doing a factory reset without restoring any my my data.  It doesn't work well at all.  After the factory reset, and reinstalling both the Amazon app and the Audible apps, they are so slow as to be unusable.  Is there a better way to do a factory reset than through the System > Reset options >Erase all data (factory reset)?

Performing a factory reset via Android settings app is the recommended way. When using other methods (e.g. from recovery you may end up in the Factory Reset Protection asking for your last Google password).

After a factory reset the device does a lot of work in the background this will make the device seem slower.


text:
What are the various ways an Android phone can be locked?
I ask this question because the confusing terminology of different types of "locked" and "unlocked" like rooted and not rooted, Sim-locking, FRP locks, lock screens, ADB active debugging, and black listed phones, and even carrier locking. These are very confusing.
Can someone disambiguate this for me?

Rooting is the process to modify core OS components so that apps/processes can be run with high privileges (UID 0).
See details in How Magisk works? and How to manually root a phone?
Rooting is not itself locked or unlocked. But Unlocking Bootloader is usually a prerequisite. Bootloaders are the initial components which load on device boot. OEMs lock them so that to restrict any deliberate or malicious changes to core OS components.
See Is there a way to root an Android phone without unlocking the bootloader?
Initially it was possible to unlock bootloaders just by issuing one or more fastboot - Android's standard protocol to communicate with bootloader - (or equivalent) commands. However now many OEMs, including Google, add an extra layer over bootloader unlocking called OEM Unlock. It's a toggle switch in Developer Options (in Settings app) which is a prerequisite to bootloader unlocking. That is, a thief won't be able to unlock the bootloader and refresh the device to completely new state (e.g. by clearing FRP, see details below) until the screen lock is active.
Also some OEMs may require the user to get approval from OEM before bootloader unlocking, others may provide no option to unlock bootloader at all.
Screen Lock backed by a password or PIN or biometrics is the one we are all familiar with. It restricts unauthorized use of (at least many of) device features. On older devices this was only software-based. New devices provide hardware backends (like TEE and SE) to store credentials more securely.
Factory Reset Protection ties the Google (and/or OEM) account to the device. This info is saved to a secure place (usually a tiny partition) on the device and cannot be erased by doing factory reset, flashing ROM or flashing Factory Firmware. After Factory Reset user is asked to enter the previously entered account's credentials. So FRP is more focused on anti-theft protection. Some OEMs disable FRP when OEM Unlocking is enabled (but it doesn't matter when bootloader is unlocked).
Also some OEMs now go even beyond that, and they'd ask lockscreen or account credentials before performing Factory Reset.
SIM Lock can be either SIM Card Lock or another term for Carrier Lock. Former is independent of Android or the device it's being used in. SIMs are Secure Element chips i.e. they have their own processor and OS. You can set a PIN lock on SIM to restrict any unauthorized use.
Carrier Lock or Network Lock binds a phone (or some other device) to a carrier i.e. a service provider. This bond is usually a part of device purchase agreement, and may end after a fixed time period. There also exist ways to do Carrier Unlock, which may not be legitimate.
See How does carrier/network lock work? How is it implemented?.
Not sure in which context you are referring the term black listed phones. IMEI blacklisted? IMEI is device's unique ID which the carriers may use to block a device from using their services after the device is reported lost or stolen or involved in some misconduct. IMEI/ESN blacklisted phones might or might not be unlockable depending on the reason of locking, the carrier's policy, and the availability of unlocking hacks.
See this answer for some details on device identifiers.
ADB Debugging is Android's standard way to let ROM and app developers communicate with Android device from a PC over USB or Wi-Fi connection. End users may also use ADB shell (like any other UNIX shell) to issue commands. ADB has no direct relation with any (un)locking mechanism.


text:
Stuck in Bootloader
I have a rooted Pixel 2 XL that I was upgrading the OS on and when I attempted to do a sideload for TWRP, it got all messed up. Now it won't go past the bootloader and keeps randomly rebooting while on the bootloader. It appears to not read fully via USB, as it either shows the SN or ??????????? when I do fastboot devices. I've tried reloading a new bootloader to no avail. I'm also unsuccessful at flashing a new OS. Hoping someone can help.

do everything you can to get fastboot working! use official tools and drivers. try different usb-cables, computers with windows/linux. unzip stock ROM run 'fastboot flashing unlock_critical' and 'flash-all.bat' Do NOT re-lock bootloader


text:
How to disable sound during screenshot in Android 11 on Pixel 3?
I've already followed the steps here (although modified a bit, since I think that example wasn't using Android 11) to disable screenshot sound notifications:

But the setting seemed to have no effect.
There is still a sound whenever I take a screenshot by holding the power button and the Volume Down button.
How can I disable the sound?

Did you try 3 finger screenshot. Do they too make noise?

This is not possible unless:

You have root access (delete the sound file), or
Use a 3rd-party trusted screenshot app, or
Disable system sound (yeah, it will disable notifications sounds and all too)

I'd recommend you to use a 3rd-party app (you can use power and volume button to take screenshots by the app by over-riding system's screenshot system). You can try Screenshot Assistant from F-Droid, or Screenshot or Screenshot sharer (super helpful if you don't use Google Assistant much) from F-Droid. FYI, F-Droid is super trusted.

The Silence option refers to the notification you see with the preview of the screenshot. Try editing some other options in there (try making it alerting and then enable 'Pop on screen'). You will see what I mean. And yes, you're correct in saying that setting it as Silence or Alerting doesn't actually make a difference to the sound - it doesn't occur anyway.
There is no user facing control to silence the sound emitted while the screenshot is being taken.

Source - Pixel Phone Help - How to turn off screenshot noise


text:
How to flash firmware from XperiFirm? Can Newflasher save user data?
My phone is stuck in a bootloop and I would like to try to fix it by flashing stock firmware. I used XperiFirm to download firmware. But then in Flashtool it won't load. I tried going to tools -> bundles -> fileset decrypt but it just doesn't load it.
I'm running Windows and noticed a part of Flashtool was detected as a trojan. I made an exception and reinstalled so this shouldn't be a problem.
I tried clicking on the XperiFirm button directly inside Flashtool, but it really quickly flashes and goes away without doing anything (nothing is even added to the log).
I looked into using Newflasher but am wondering if there's a way to save data? I would like to do a dirty flash.

have you tried Androxyde Flashtool?
https://www.hardreset.info/devices/sony/sony-xperia-xz1-compact/faq/firmware-flash

@alecxs yes that is the one I mean. I'm unable to do step 3) simply nothing happens. I've tried already but is there an additional step, for example must the phone be connected in a certain mode for XperiFirm to work?

ask in support forum Androxyde Flashtool

found following instructions: 1) Unzip FTF file, extract the system.sin
2) Dump system image from system.sin with Flashtool
-> Advanced-> SIN Editor 3) rename system.ext4 -> system.img

I got the stand alone XperiFirm to work. How do I know which version of the firmware to download? I had Pie working so guess it's 47.2 but I don't know what the last 3 characters mean e.g. 47.2.A.11.228-R2C or  R7C My country isn't listed under "Market" but I'm planning on going with a customized US or UK.

After running grep version /system/build.prop I get the result with first line ro.semc.version.fs_revision=47.2.A.4.41 For some reason XperiFirm doesn't have this version, but I found a download to it from the Sony website. The download comes in a bz2 which contains tar which contains all the folders including system. I'm not sure how to flash these files in this format...

after rethinking just flash 47.2.A.11.228 (don't know meaning of -R2C) encryption doesn't matter anymore (because you already have unencrypted data.ext4.win on PC) also TWRP is always bootable from fastboot for emergency: 'fastboot boot twrp-3.3.1-0-lilac.img'

Let us continue this discussion in chat.

I couldn't get the XperiFirm integrated into Flashtool to work. Even with the stand alone, it didn't have the firmware I was looking for. I ended up just Google searching the the firmware with "ftf". Flashing it with Flashtools worked fine.
TL;DR download the desired firmware as an FTF found through a Google Search. Flash it with Flashtool.


text:
Stop Notifications when the App is closed
This may be a stupid question since the Android is maybe supposed to work this way, still though I am wondering if this is possible.
Two apps, Microsoft Teams and Outlook are sending the notifications when the app is "closed". Now i would like for that NOT to happen when the app is closed. Is there any way whatsoever, that i can stop the notifications when the app is "closed"? I understand that the app is probably always running in the background and that until force stop it is never really closed. I am just wondering if I am missing something that can be chosen in the notifications settings that i havent found yet.
Also, i do realise that you can choose the "quiet hours" in the App settings itself, but that is not something i am looking for.

Push messages by design can wake-up (or even start) the app they belong to. The only chance to silence them is the "Do Not Disturb Mode" or if the app supports a different processing of push messages during certain hours.

Hello Robert, i was afraid you might say that but thank you for clearing it up for me!

You can block notifications of specific apps with Automate app. Tell me if you are okay with using a 3rd party app

@velvethadron If you want an app to not show any notification at all, you can long press the app -> go to app info. -> notifications -> and deny permission

So far I've found three ways to prevent notifications:

Remove the app. -- definitely not useful 99.9% of the time

Or, as you found out, kill any process that app. is running

The app. itself has some settings, including whether to send notifications or not

In the global Settings, go to Applications, search for the App, check the Notifications there and turn off what you do not want to be notified about

(1) is not likely what you want, (2) is rarely implemented and (3) is usually rather limited... so in many cases, it won't help you much. That being said, (3) can be an app. savior.
As Robert mentioned in a comment, the Android OS works by automatically waking up / starting applications when they receive messages if they were not running at that point. When installing an app., it can register the events it is interested in and it will receive them no matter what (nearly). And notifications work that way too...
In the cases you mentioned, it may require a poll() by the app. In that case, the app. has to be running. In generally, a very small amount of the app. gets loaded, just enough to handle the necessary code to run the polling. If the app. doesn't offer an option to turn that polling off, then it just won't go away without uninstalling.


text:
How can I delete from my smartphone the images downloaded by Google Chrome from the internet, which I can't find anywhere?
I have a A3 Umidigi smartphone, Android 9. I downloaded the images by Google Chrome (search images engine), and I can't find them in any folder (included Download, Pictures or DCIM), but I can see and use them as backgrounds (actually I use as background one of these downloaded, invisible images). I searched them using the App "Total Commander" (and other similar), and I connected the smartphone to the desktop by usb cable, but I couldn't find them. Google Chrome has access to the drive. Now, if I download another picture, Chrome asks me where to save it, but I have a dozen images I can't find.
Download folder (without the downloaded pictures).
Download options in Google Chrome (without the pictures).
"Background" selector: I can see and select the pictures (even offline). By the way I can't find any App named Background or whatsoever.
Root folder
Root/data/data folder
Root/system folder
data/com.android.chrome/files/Download folder (empty)

Did you look for it in the Downloads option in chrome? (not the "system download' app)

Wallpaper once set is saved to /data/system/users/<User_Id>/.

I looked for in the Download option in Chrome, but there aren't. I can't find the exact folder Android\data\system, or data\system, but only Android\data... (with many subfolders such as ...\com.google.android.apps.docs).

I added three screenshots in the question: the Download folder, the Download option in Chrome, and the Pictures in the background application. Only in the latter I can find the pictures.

@Mishima /data/system is in the root folder. This is not the same as the Android/data folder you access from your internal storage.

What is the download location shown in Chrome?

I noticed the "root", now. I have the folders root\data and root\system but not root/data/system.
In root\data there is the folder root/data/data/com.ghisler.android.TotalCommander
In root\system there is a \usr folder (not user), with the following subfolders: hyphen-data, icu, idc, jeychars, keylayout, share, srec.

The download location shown in Chrome is Download/storage/emulated/0/Download, but I can't find the files there (it's before the root folder). On Google Chrome now I have the option Ask where to save files on.

In the folder /data/data/com.android.chrome and its subfolders, would be the place to look. You will need superuser permission to be able to access this folder. In Total Commander start File System Root.
For example /data/data/com.android.chrome/cache/image_cache Has picture files. Actually all the files in there are pics even though they have no extension.

I found the folder Root/data/data/com.ghisler.android.TotalCommander (with an empty /files folder inside), but not Root/data/data/com.android.chrome.
There is the folder storage/emulated/0/Android/data/com.android.chrome/files/Download, which is empty.
Maybe I have no permissions...

Is your devic rooted? If not that would be why you see an empty folder. Without root permission you can't access inside that folder.

I don't know if the smartphone is rooted. In case, how can I check and have permission to access the folder?

If you didn't root it it's probably not rooted. There is an app on google play that checks if your device is rooted. Root Checker

I installed the App, and "Root access is not properly installed on this device".


text:
Xiaomi Mi Band 2 cannot be paired with App Mi Fit in Android 8.1.0
I wanted to pair the LG Q6 with the Mi Band 2.
I installed Mi Fit, created a google account and wanted to pair with the device. However, after a while, an error is displayed stating that it couldn't be paired and if I want to reset the device.
If I select yes, the 4-digit number will be displayed on Mi Band 2. A window with a box where I should enter the number will appear on my mobile phone. However, this window is partially covered by another error message that it cannot be reset and whether to cancel or resend. In any case, this window cannot be hidden, so it was not possible to write the number.
So I uninstalled and installed the application, but the only thing that has changed is that the reset fails and the number doesn't appear on the device at all.
Please help
Thank you
PS. Android itself can be paired with the device.
UPDATE
I searched for a solution and found a link to Fix-it for Mi Band 2. Although it has a low rating, I still tried. I followed the instructions and everything seemed fine, but it didn't help.
I would be grateful for a solution, but I personally gave it up.

I have the same problem. Did you solve the problem or did not? If you solved, would you share with me the solution? Thanks.

@Yagiz I'm very sorry for the delayed answer. I wrote everything in answer to the question - it was enough to use another application.

So in the end, the solution was incredibly easy. At the time I was trying to pair it, it never occurred to me to try anything other than the official app. But since then, I've found that the official app may not always be the best. And here it was the same - it was enough to use another application - Mi Band App for HRX, 2 and Mi Band 3.
I haven't tested it yet, but the pairing itself worked, so hopefully there won't be another problem.


text:
How to make a complete backup from rooted device to non-rooted device?
I would like to get my data from an old rooted android phone, to a new android phone which can't be rooted. adb backup and helium aren't able to get all of my data from my rooted phone.
Is there a way for me to use the power of root in my rooted phone to make a backup, and then through non-root means restore the backup to the non-rooted phone?

Does this answer your question? Transfer Android app with offline data to NEW PHONE without ROOT

no… unfortunately it just suggests adb backup, which i already tried

@əkaunt Unfortunately restoring app data of apps that disallow adb backup on an unrooted device is not possible.

@Robert do you think it is at least possible to set allowBackup directly on rooted phone without changing signature?

@alecxs I would assume yes as most properties from AndroidManifest.xml are cached in one or two central XML files. Unfortunately at the moment I don't remember where to find those files and their names.

@Robert I'd assume packages.xml being one of those. But still, not sure if the target will reject that as it gets the "no" from the APK (not from the XML it does not (yet) have).

@alecxs mtk-su failed on me… but setting allowBackup to true on the rooted device might be an option. I'm eagerly awaiting your answer

didn't find anything useful. guess it's not possible to change config on runtime https://stackoverflow.com/q/12870148

maybe it's possible to compile insecure com.android.commands.bu to ignore manifest? but the more interesting is still the restoring process on the unrooted device. will restoring work for matching signature with allowBackup=false? if so, that's worth a try

unfortunately that's pointless If someone
produces an apparent restore file with data for such an application,
it will not actually be restored onto the device

is it possible to recompile adb so that it doesnt check allowBackup and just backs up all programs regardless?

you probably didn't read the post from Nikolay Elenkov i have linked in comments. It's all written in java


text:
Upgrade LG V35 Thinq to Android 10
According to many sources, Android 10 was released for the V35 earlier this year.
According to (the only US carrier for this phone) AT&T's website, the most recent version for this phone is Android 10 at the May 2020 patch level. (Confusingly, that same page also says it is still only Android 9.)
However, my phone says it is on Android 9 with the July 2019 (!!) patches being the last that were applied, but when I check for updates, it says "Current software is up to date".
These updates appear to only be available from AT&T over-the-air, not from LG directly, and this phone no longer has service (I use it for app development and as a music player) so AT&T can't/won't help me.
Is there a way to update this phone?

This isn't the first time we read here about problems regarding of AT&T devices not receiving updates. Unfortunately from my perspective there are only two "solutions": 1. Get yourself an AT&T data plan and/or 2. Never again buy a branded device from AT&T.

@Robert I suspected that. Samsung phones on Verizon are the same. Apparently, just having AT&T service isn't enough - I put in a FreedomPop SIM card, which is actually AT&T service and says AT&T as the mobile network displayed on the phone, but AT&T apparently doesn't see that as enough. I will probably find a friend or neighbor with AT&T service and try to borrow their SIM card for a few minutes.

A Wifi hotspot (for connection sharing) opened by an AT&T device should be another option. That would enable you to use an AT&T network without having to get your hands on the SIM card.


text:
Is this possible in Android that a file/folder can have multiple owners and group?
So in my scenario, I am trying to assign multiple groups, the user to a file in /dev/. So I have created a custom AID in config.fs and the corresponding [path], mode, caps parameter also configured. Also modifies my apk to uses this new gid.
At runtime, I saw that a custom group is created and my process(java process) also has this custom gid in Groups(cat /proc//status). But still, I can't perform the operation on /dev/* file.
So my question is this possible in android that a file/folder can have multiple owners and groups?

not sure about mounted namespaces, but in linux world subgroubs can be members of groups. on file system level you can only chown single group

I don't know of any OS where a file is owned by multiple users or groups. You can have multiple supplementary groups though, or something like ACLs. Not clear what you are trying to do. From config.fs I guess you are developing a ROM? That's off-topic here. And you talked about DAC only. What about MAC (SELinux)?

@IrfanLatif ok to elaborate more in android /dev/snd/pcm* is owned by user system and group audio. just for some reason, I want to access PCM device from an apk. instead of assigning the full audio gid permission I thought to create a custom gid and have this gid also in /dev/snd/pcm.


text:
ERROR Unable to retrieve local hardware address libnet (ioctl: Permission denied). iptables (2) failed
hi I tried to install network spoofer but it gives me this error and not only with this app but also with others it knows how to solve I already have the root

Duplicate of https://android.stackexchange.com/q/221649/218526

Does this answer your question? how to fix ioctl permissions denied error?


text:
Getting back to the first-time phone transfer wizard without factory resetting
During the first-time setup process, Android asks to connect my new phone to my old phone with a USB cable. I'm not ready to transfer yet but I want to test drive the phone. Is there a way to get back to that transfer wizard?


text:
Is it possible to attach phone with USB c port to PC and 3.5mm audio out at the same time
I have a google pixel 3. It only has a USB c port, no 3.5mm audio jack. I would like to be able to connect my phone to a PC via usb to enable adb access and at the same time get audio out of the phone with a usb c to 3.5mm jack type adaptor. I had thought that I could achieve this with an adapter like this:

However, I got one of these and while the audio output works, the usb C connection only allows charging and no data connection to the pc. I was looking at usb c hubs but I am thinking that these would only work with the phone as the host/master and the devices plugged into it as slaves.
Is there any way to achieve what I want?
The reason I want to do this is in order to use scrcpy to remote control the phone from the pc while also getting audio out of the phone.

You can use scrcpy over WiFi as a workaround (assuming you don't want to use Bluetooth audio).

Yes I am aware of that, sorry I should have mentioned in the question, but there is usually a reduction in video quality and/or lag compared to usb so I was hoping to use usb.


text:
Is there a way to give permissions temporarily?
Is there a way to take away permissions when i leave an app? i dont have root and also no intention to root. is it possible to do this with adb or something??

As far as I remember this is a new feature of Android 11 e.g. for location permission. Google calls this One-time permissions.

I have already asked this question Is there an alternative to Bouncer- Temporary app permissions?
I found a temporary solution.. using automate app. You can use its interact block to automate the steps real easy. But it only works when the element is visible. That means we will have to scroll manually. Rest all is easy!


text:
Background apps not working
I use this app on SM-J7 with Android 8 to check my internet connectivity. I hardly use this app as I get to see what I require in the notification bar. But every day, I am forced to manually open it to make it work.
I also face the same issue with this but this one works fine, although both of them run in the background.
I have installed the same apps on another device (SM-M30 with Android 10) but there the apps start working on their own after the phone is switched on.
What is causing this? Any remedy?

Without knowing your device, have you checked the guide on Don't kill my app!?

@AndrewT. As per its suggestion, I disabled the app from the list of battery optimisation. Still, no result :(


text:
Unlocking the bootloader Huawei P8 Lite 2017 (PRA-LX1(C02)
I'd like to have my bootloader unlocked for my Huawei P8 Lite 2017 (PRA-LX1(C02)), but I don't wanna spend money on DC-Unlocker. My phone runs Android 8.0 EMUI 8.0 but I can downgrade it to Android 7.0 if needed. If you need IMEI, Serial Numbers things like that ask me and I'll provide those.
Thanks in Advance!

so your question is where to get unlock code for free

basically yes if you know where I can get it please tell me thanks


text:
Editing adb backup files
I want to edit the contents of an .adb backup file. I found a command to extract the contents:
dd if=mybackup.adb bs=24 skip=1 | zlib-flate -uncompress | tar xf -
I edited the extracted files as needed but how do I build adb files with the modified files?
I thought of streaming the directory, compressing it with zlib-flate and generating the tar file. Is it possible?

In my opinion the preferred way for extracting such backup archives is Android Backup Extractor (abe) (requires installed Java Runtime).
It allows to convert adb backup archives to tar files and also the reverse way to convert TAR files back to an adb backup files that can be restored via adb:
java -jar abe.jar unpack mybackup.ab mybackup.tar

Modify created file mybackup.tar.
java -jar abe.jar pack mybackup.tar mybackup_mod.ab
adb restore mybackup_mod.ab

https://forum.xda-developers.com/showthread.php?t=1572600&page=2

actually, it still works on my huawei p smart.


text:
Restoring the /data partition on Android 11 yields an unlockable phone
I have a Xiaomi A2 which went into a bootloop due to a buggy Android 11 OTA update. It's a bug in the update, and a lot of people are affected.
My phone really had a rather vanilla setup (original Android One ROM). The only exotic thing I did was to unlock the bootloader. Everything else is untouched.
When I installed the Oct 2020 OTA update (version V11.0.15.0.QDIMIXM) my phone went into a boot loop. So I booted on TWRP from fastboot, and using adb pull /dev/block/mmcblk0p69 data.img I got an entire disk image of my data partition on my PC.
Using fastboot I then flashed the previous known-working OS version (version V11.0.14.0.QDIMIXM) but then when I boot my phone I now have a weird problem: my PIN isn't recognized anymore! If I try and remove /data/system/locksettings.db from TWRP, then it does remove the PIN and I can "log in" with a swipe, but then the phone gives me a never ending spinner. I assume something is wrong with File-Based Encryption and the fact that I didn't provide a PIN.
Question: why is my PIN not working anymore? How can I get it to work?

Does this answer your question? Xiaomi A2 stuck in a reboot loop because of data partition


text:
How to enable an "Always on Display" mode in Nokia 9 for JUST notifications?
In Nokia 9 with Android 10, I set Settings=>Display=>Advance=>Screen timeout to 30 seconds, but I still like be aware when I have notifications waiting to be reviewed.
In Settings=>Display=>Advanced there are Glance view options:

The default Glance display duration is 30 seconds. But I like to see all of the notifications which I missed when I wasn't around my phone, so I've changed it to Always on...which got the screen to be constantly on!

True, it's not "fully" on. It's a black screen with a clock and battery percentage. But is there any way to keep the screen completely off and only keep the glance screen on if I actually have notifications waiting to be reviewed?
In other words, see how Wikipedia describes what I want:

Typically, an Ambient display solution which turns on the screen only when notifications are present, remains on, but turns off when they are dismissed.
- Always on Display, Wikipedia

Here is what I get when the screen is supposed to be turned off:

Based on my experience on Nexus 5 on LineageOS 14.1 (Android 7.1.2), Ambient Display only turns on the device for a brief moment when a notification comes, then turns off itself. The display is not permanent on though when there are pending notifications.

As mentioned, the default is indeed 30 seconds. But you would think changing it to Always on (see new screenshot) should fix it. Alas, it just causes to be on 24/7.


text:
Encryption: can't decrypt data after rom downgrade
I downgraded an Android 10 custom rom while I had encryption enabled (rom).
Basically I dirty flashed a previous minor version of the rom via TWRP (with just a simple "wipe cache/dalvik").
After the reboot my pin was not recognized by Android (and TWRP), so I could not access any data.
After a few tentatives I typed "default_password" as pin, when asked during the boot, and there was an important change:

After the subsequent reboot I typed my original pin, and now Android always shows: "The password you entered is correct, but unfortunately your data is corrupt". This happens every time at the system boot, and it won't let me type any pin.
TWRP accepts the original pin, but it's "unable to mount storage". If I type "default_password", or anything else, it's not valid.
In TWRP the system partition's contents are now visible: before they were not showing at all. But the data partition is not accessible (error decrypting…).

I have done a lot of studying to get the phone working without formatting, but I could not solve the issue. I don't think the data is actually corrupted.
I read that there is a Android security mechanism called "version binding": "Version binding binds keys to operating system and patch level version", … "any reversion of the device to a previous release causes the keys to be unusable".
This could explain what happened, but I have many doubts.
Knowing this, I flashed the original version of the rom (the one I had before this issue), but nothing changed.
I took a look at logcats and recovery.log and I noticed the following message: "Error starting keymaster signature transaction: -21".
Here is a extracted part from a recovery log, after I enter the pin in TWRP:
I:Is encrypted, do decrypt page first
I:Switching packages (TWRP)
I:Set page: 'decrypt'
I:Set page: 'trydecrypt'
I:operation_start: 'Decrypt'
D:crypt_ftr->fs_size = 52453304
I:starting verify_hw_fde_passwd
I:Using scrypt with keymaster for cryptfs KDF
I:TWRP keymaster max API: 1
I:Signing safely-padded objectkeymaster module name is Keymaster QTI HAL
keymaster version is 256
Found keymaster1 module, using keymaster1 API.
Error starting keymaster signature transaction: -21
E:Keymaster signing failedE:scrypt failedI:Extra parameters for dm_crypt: fde_enabled ice
I:target_type = req-cryptI:real_blk_name = /dev/block/sda14, extra_params = fde_enabled iceE:test mount returned 0
I:Found no matching fstab entry for uevent device '/devices/virtual/block/dm-0' - add
I:Found no matching fstab entry for uevent device '/devices/virtual/block/dm-0' - change
Data successfully decrypted, new block device: '/dev/block/dm-0'
I:Can't probe device /dev/block/dm-0
I:Unable to mount '/data'
I:Actual block device: '/dev/block/dm-0', current file system: 'ext4'
Updating partition details...
I:Can't probe device /dev/block/dm-0
I:Unable to mount '/data'
I:Actual block device: '/dev/block/dm-0', current file system: 'ext4'
I:Unable to mount '/usb_otg'
I:Actual block device: '', current file system: 'vfat'
...done

Could you please point me to the right direction? I am trying to understand what could have gone wrong, and find some possible solution.
How is the pin still accepted as correct, but not able to decrypt the data?
I think that there is something that prevents it from working.
I can recompile the rom with my own modifications if needed, and post other logs. Thanks for any help.

Additional logs.
the partition is still encrypted
hexdump -C -n1088 /dev/block/dm-0
00000000  06 27 35 9d 5e 75 e0 ff  e0 53 2d 23 f4 99 d3 9d  |.'5.^u...S-#....|
*
00000400  8c cb fb 69 ad 08 1f 75  03 b1 4c 51 54 84 c6 b2  |...i...u..LQT...|
00000410  f4 f2 c9 75 b8 72 e5 f4  68 76 81 16 a8 cd 33 c8  |...u.r..hv....3.|
00000420  e4 64 c4 70 5f 56 55 72  24 3c 44 dc 5e f0 4d 9b  |.d.p_VUr$<D.^.M.|
00000430  05 ca 91 e3 52 b2 09 2b  b0 0c 8b 32 13 2c c2 3d  |....R..+...2.,.=|

compared to a ext4 image (magic 53 ef at offset 0x438)
00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000400  e0 33 18 00 f3 bb 60 00  00 80 00 00 6c a0 2a 00  |.3....`.....l.*.|
00000410  9c 16 17 00 00 00 00 00  02 00 00 00 02 00 00 00  |................|
00000420  00 80 00 00 00 80 00 00  f0 1f 00 00 bd 76 59 5d  |.............vY]|
00000430  bd 76 59 5d d1 00 0a 00  53 ef 01 00 02 00 00 00  |.vY]....S.......|

just restore the TWRP backup from previous state and encryption is working again

The TWRP log indicates that it is trying to decrypt a Full Disk Encrypted data partition, which would be unusual for an Android 10 device. When you booted (as everything was working) your phone when does the does the password prompt appear, as the very first action before the phone has fully booted up or later when the background and the lock screen are already loaded? If it is the latter the device uses File Based Encryption and therefore the decryption fails.

@Robert I think this rom uses FDE because the phone (Mi5) is not Android 10 native. "adb shell getprop ro.crypto.type" returns "block"

@alecxs I don't have that backup. Anyway I already flashed the original rom via "Adb sideload" but nothing changed.

i think it's a duplicate of https://android.stackexchange.com/q/224440 but the message "Data successfully decrypted" is misleading and your issue is different from mine, answer is invalid. after reading your linked google stuff i guess your keys are already marked as invalid and there is for some reason still anything inside qseecom stuff that a) tells twrp the keys are correct b) but on the other hand garbles decryption because of the invalid-flag (all just guesswork)

@alecxs Thanks, I was also thinking that the key was marked as invalid after the downgrade. But by looking at the error codes (keystore error codes), I think it would use a different one instead of -21 (KM_ERROR_INVALID_INPUT_LENGTH). I am adding the hexdump log in the first post.

inspect the crypto footer with python script you can't decrypt but maybe you will find some flag you can reset to 0 (although i don't believe it's that easy). install python and run this script: 'python.exe bruteforce_stdcrypto.py [header file] [footer file]'

@NikolayElenkov recently we figured out how to reset failed decrypt counter in fde crypto footer. We invite you to join our conversation regarding other flags https://forum.xda-developers.com/showthread.php?t=4168821


text:
Company owned devices options for system apps
My questions regard the possibility to temperate which phone application could be set up while using Google Workspace (or any other MPA). Specifically: can I set up an application to replace the phone system app?
I've read this but does that means that I can't disable the phone system app? Or that the com.android.phone package is the system app.
Another solution would be to get controls over the default apps settings and lock the employee out of these ones. The MPA solution would then be able to enforce the use of another Phone App as being the default system one. I could not find any documentation covering this.

My interpretation of https://support.google.com/a/answer/7292363 is that
com.android.phone is a system app that cannot be disallowed
However you can create a policy which will prevent non-emergency calls:

4.24. System radio management
4.24.5. IT admins can configure whether the device can make outgoing phone calls, excluding emergency calls (see outGoingCallsDisabled).

At which point you can put your own Phone app on the device. Note limitations on Phone apps that developers are bound to.
So presumably the device will still have the Google phone app but that app can only be used to call emergency services.

Nice, that would do for outgoing calls but still, that doesn't mean I can enforce incoming calls to be answered only through a phone app replacement, an employee could still modify the default app settings to choose the system one.

I was under the impression that your devices would be using a VoIP system, https://developer.android.com/work/dpc/network-telephony.html#third-party_apps_must_implement_connectionservice, but if its over a mobile voice network, the mobile provider should have audit capability and perhaps even some controls.

I can't use VoiP here, the project is for a financial institution which, due to some regulations, is forbidden to treat calls over the Internet, so the solution I need to provide is SIM-based only. Tuning the mobile provider would mean something entirely different. What I'd need is this: https://developer.android.com/reference/android/telecom/InCallService#becoming-the-default-phone-app with no turning back (except at an admin level)


text:
Wrong aspect ratio for video sent with WhatsApp (only when trimmed)
When I take videos with my Sony Alpha 5000 and transfer them to my Android device, the aspect ratio looks fine in all players tested (F-Stop, VLC, MX Player Pro, ES Media-Player).
When I send such a video with WhatsApp and keep the full length, it still looks fine. But when I change the video length in WhatsApp before sending, the video will be sent with a wrong aspect ratio (squeezed):

(Top message: full video; second message: trimmed video played with a wrong aspect ratio)
This is a link to the video in case you want to reproduce what I did:
https://www.dropbox.com/s/ovp1j9mmb49exq2/MAH05890.MP4?dl=1
Has anybody observed this issue, too? Is something wrong with my video file?
EDIT:
I have recorded another video in landscape mode and replaced the original screenshot/video link in order to make clear that this issue is not related to a wrong video orientation in this video's metadata.

Looks to me more like a landscape/portrait problem. My guess would be that the video contained a marker that it has been recorded in portrait orientation and the WhatsApp video editor has removed the flag which makes the video players display the video in wrong orientation.

I see the wrong orientation in every video player. It looks like WhatsApp can't rotate videos. But meanwhile I found an app called "Smart Video Rotate and Flip" that can rotate my video by just changing metadata. But even with the right orientation, WhatsApp squeezes my video when I trim it.


text:
Unable to connect to wifi on Nvidia Shield Portable
Recently picked up a used Nvidia Shield Portable to play around with. Digging it so far, but it refuses to connect to my Netgear Nighthawk MR60 Router and I'm not sure. Right now I have to tether off my phone just to use internet. I'm running stock android 5.1 with the latest updates
Best I can figure looking at the logcat logs from ADB is that it has something to do with this line.
W/wpa_supplicant(  583): wlan0: WPA: Failed to configure IGTK to the driver
I/wpa_supplicant(  583): wlan0: RSN: Failed to configure IGTK

I don't have my device rooted, so I don't know if I can disable PMF in the wpa_supplicant.conf. Any ideas?

Did you try rebooting the device?

Yeah, I've tried rebooting the device. No luck with that. I'm currently working on getting root access to see if I can fix it with that

I've now rooted the device. I went to the wpa_supplicant.conf files in both /system/etc/wifi/ and /data/misc/wifi/ and set pmf=0, however the file in data just resets pmf=1. I tried rebooting the device again after this but that changed nothing


text:
Can one app access an app that has password protected?
On my Android, there is a feature that I can set password for app that I want to. Example, let's say I set a password for my gallery and then I install new app from play store or browser and the new app want to access my gallery. Can that new app access to my gallery?

What is that feature?

the feature is in Huawei phone and i don't know what it is. I just know that I can set password for app in settings.

Then it will all depend on the limits of that feature.

Password protection for apps usually protects their UI i.e. the activities won't appear in foreground without authorization. Such kind of protection doesn't protect app data. In case of gallery, the data which the app shows i.e. photos, videos etc. isn't owned by the gallery app. So even if the app is protecting all of its private data (e.g. by encryption), photos and videos are lying on shared storage. And any app with Storage permission can access that data.

No, The other app wont be able to access this app but other app can access this app data if its not stored encrypted on device storage. Other app only need storage permissions to do that. If other app can access device storage then that app can access any unencrypted data stored on device. But it wont be able to access OS files which are stored in read-only partitions/folder without having root access


text:
Lock computer USB connection with anther password
I'm looking for a way to lock computer USB connection with second password, not with the regular lock screen password but with a different password. Thus, people who already know the password of my device will not be able to transfer files and connect it to the computer without the other password.
There is an app on the play store that called:
Smart AppLock (App Protector)
https://play.google.com/store/apps/details?id=com.sp.protector.free
It has the so-called option "USB Connection Lock", but it isn't working... Is there a similar way to do it? I searched the internet but did not find anything close.. maybe some code to use with ADB?

You need an app or a way that detects whether com.android.settings/.Settings$UsbDetailsActivity activity is in the foreground or not. If in foreground, than create an overlay or a new activity on top of it which would act as a password lock (the type of which you are seeking). So far, I have not been able to find an app that offers detection of a specific activity launch.

I'm not a developer, so what can I do?


text:
Touch screen not working on some screens even after factory reset
My touchscreen no longer works at all, on MOST screens.
However, there are some screens where the touchscreen consistently works perfectly, so it is extremely difficult to believe that this is an issue with the touchscreen.
The screens where it always works without a problem:

On the lock screen where I swipe up and then enter in my pattern.
The menu that appears when the power button is held for a second or two.
The home screen, where I can swipe left/right and navigate my app list.

My device is the Sony Xperia L3 and I'm using the default launcher.
After factory resetting my phone, the problem persists. I cannot get passed the setup screens. However, once again, the menu that appears when the power button is briefly held works perfectly. I can tap any of the 3 buttons, or tap away, every time.
I dropped my phone 10 months ago and there is a fairly big crack at the bottom right of the screen, and a tiny hole which seems to lead in to the internals. Up until now, it's been working fine. Not only is the touchscreen now acting up but the pixels on the screen are very glitchy.
Any ideas what the problem is and how I can fix this? Again, I'd like to reiterate that for some bizarre reason the touchscreen works fine on certain screens 100% of the time, so I'm hoping that there is some solution without requiring repair or getting new phone.
One possibility why the touchscreen works on some screens and not on others is the following: Perhaps there is a small section of the touchscreen that is constantly being tapped on because of the damage. This would mean on some screens, it thinks I have two fingers on the screen, and thinks I'm trying to zoom and therefore won't let me do anything else. On other screens, it is coded in a way that ignores the second finger.
However, with this possibility in mind, I tried installing the "Partial Screen" app. This allows me to disable the touchscreen on certain sections of the screen. I tried disabling the top half, with the bottom half still broken on the screens where it normally would be. I then tried disabling the bottom half, with the top half still broken on the screens where it normally would be. When I first started the app, it tried to scan areas of the screen with a problem and none were found. So this is making me believe that there is no issue on the touchscreen with areas being constantly tapped on.


text:
Contact that cant be made a favourite
In my contacts on my Samsung phone I have a contact that I cant "star", other contacts have that star you can click on to make them a favourite but this one contact that just isn't there. I've tried creating a new contact but it just won't let me make her  a favourite.
Any idea why?
Thanks.
Edit:because I can't add comments.  Its a Samsung S10e OS ver G970FXXU9DTJA

Hello. Which Android version and Samsung device are you using? Can you post (in a manner hiding the identity of your contact) the details that you have added into this contact?

Hello @CletusVanDamme. It seems that you have lost access to your account with username Tim. You can get your current account merged with that one and get ownership of this question. Please use the contact form to have this sorted out for you. Good luck.


text:
I want to modify the user interface of android for my device, is this possible if the OEM didnt provide the source code?
The device is running android pie and i know that my build version is PPR1.180610.011 and its already currently running AOSP, however its the ALPS variation (which i think is mediatek's version (closed source)  of AOSP where they just augment the telephony based apps so it works with their HALs, while the android UI remains vanilla).
I want to modify the theming/ui parts of android (which im sure most of it resides in (system\system\framework\framework-res.apk) as shown in https://prnt.sc/vfn6r3
However as mentioned above there are some proprietary binaries shown here https://prnt.sc/vfn85h

Is it possible to build AOSP for my device (after making my desired theming enhancements) and then just migrate the proprietary binaries into their correct directories?

Or should i be looking at decompiling the framework-res.apk and recompiling it and then repacking the system img file?

P.S the bootloader is unlocked and i already have access to the unpacked partition img files
p.s installing xposed or any other theme modifying software is not an option as i dont have a custom recovery such as TWRP


text:
Do any open source Android ROMs work on smart clocks?
Has LineageOS or any other open source Android ROM moved into the Smart Clock (bedside alarm clock space)?
It seems some of these run Android Things:

The touchscreen isn't as robust as Google's other smart displays, but it uses the same Android Things software which is a trimmed-down version of Google's mobile operating system meant for smart home gadgets.

It looks as though the Lenovo Smart Clock open source software is here.  Looking quickly it appears to be the kernel only.
The device's SoC appears to from MediaTek, codename mt8167s  possibly the same device powering the Lenovo Smart Display.  (The kernel config file is called mt8167s_ref_debug_defconfig).  I don't see any device repositories on github for this, but interestingly, there is a file for Google's Fuchsia OS Zircon microkernel for this board.
Somoene appears to have put the source on github here.  He (I assume "he"- the name is "deadman96385") has a TWRP recovery repo here for the smart clock (which may actually be named iot_mt8167s_som ??) which might be a good starting point for doing a full android port.
Also, looks like he dumped the rom here.


text:
Samsung Account Notification won't go away
I recently updated my Samsung A10e to Android 10 with OneUI 2.0. When it finished updating, I got a notification requesting me to "sign into my Samsung account to safely use some services". I forgot the password so I reset it accordingly, and then I (thought that I) finished.
Except then it gives me a notification asking "we need some more information to finish setting up your Samsung account". I enter the requested information and hit "done". Then, almost seconds after hitting "done", the notification pops up again, requesting the same thing. When I go back to the screen where I was to enter information, it still showed the information I already entered, but the notification WOULD NOT go away!
Help would be appreciated, as this notification will not go away.
Thank you for your help!

I hope someone has a good answer for you.  I stopped buying Samsung devices because of issues like this.  Just because you buy a Samsung device, doesn't mean you should have to create a Samsung account.


text:
TWRP won't select USB drive with USB OTG cable
I have a USB OTG type C cable with a flash drive connected to it. The flash drive is formatted with FAT32. The phone can see it, TWRP can see it, but TWRP can't select it. In TWRP I try to mount it but when I press the option it doesn't get selected. It says "(OMB)" beside the option, but there's several GB of space available. I have an SD card that can be selected fine. I'm running TWRP 3.3.1 on LineageOS.
How can I chose to make a backup to the flash drive over USB OTG?

https://www.joom.com/en/products/5b2b0c1d8b2c37010cfa6b15

Many USB-C hubs do not need external power to work because they draw power from the computer they are connected to. However, this may mean that it will not be able to power some devices that require more power than the hub can provide.


text:
What app is org.codeaurora.snapcam?
I found this app with package org.codeaurora.snapcam showing up on my Google Activity. It say I used it, but also it doesn't show any details of what it is. It just shows details of my phone. I have Hot Pepper VLE5 phone and also a Samsung A20 which my husband uses but were on the same Google account on both phones.
My husband thinks it is a secret app that I use to hide things like messages and pictures. I love my husband very much and I know that is not true. I did some research of it but there was not many accurate answers. What I understood is that it's a camera app called camera apk, but I wouldn't know if it's that. I have seen a lot of apps on Google Play called Snapcam, but that is a photo editor and i don't use those kind of apps. So it can't be that.
I just don't know why this org.codeaurora.snapcam shows up on my Google activity saying I used it. I really need to know what this is. I'm so confused I would really appreciate your help. Thank you.

snapcam is SnapdragonCamera app: https://source.codeaurora.org/quic/la/platform/packages/apps/SnapdragonCamera. Snapdragon is the brand name of SoCs manufactured by Qualcomm and used on many Android devices. Codeaurora is the public forum to release updates for SoC components from Qualcomm: https://wiki.codeaurora.org/xwiki/bin/QAEP. You can make a web search to know more.


text:
Apps disappear from start screen but still in the apps menu
Sometimes when an app updates it's icon disappear from start screen (launcher) but still in the apps menu.
What is the reason for this and how to avoid disappearing? Samsung S7

An app can define one or multiple start icons. Each start icon is assigned with a different "start activity" (a different screen in the app).
If an app is reorganized internally this "start activity" may change. As each app icon is assigned to a fixed "start activity" the old app icon you have placed on your home screen (launcher) is no longer valid and is therefore removed.
In the apps menu always all start icons of all apps are displayed. Therefore if the start activity of an app changes the old icon is removed and the new icon is added. Often old and new icon are exactly identical and also the icon text is the same, thus it is not obvious why the icon on the start screen was removed but in apps menu it is still present.

Is there something to avoid this situation on the user or on the programmer's side?

@monok On user side there is nothing you can do. As an app developer you can ensure not to change android:name property of for main activity when publishing updates. As far as I know if you don't change this property the app icon on the launcher should remain as it is when the app is updated.


text:
Is it possible to run old apps on newer versions of Android? If so, how?
I'd like to run an older app that is no longer compatible with my current OS. However, I don't want to set my device back to an older OS. Is there any way to make old apps work with a newer OS, or is an older OS my only option?

How do you know that the app is not compatible with your current OS? In general Android OS versions can't be downgraded unless you are running an unlocked/rooted device.

The app is no longer available in the current play store, and crashes when I try to run it on the current OS. I do know how to downgrade my device, I just don't want to.


text:
TWRP can't access internal or SD storage (0MB) after crash+bootloop on LG G3 D855
After a random system crash my rooted LG G3 (D855) fails to boot into android (Android 10, Lineage OS, boot loop). As I have a recent backup on my SD card, I'm trying to restore to that in TWRP (3.4.0.0) but here's the problem - I can't change storage to the SD card where the backup or any other files are - TWRP shows "0MB" both for Internal Storage as well as for Micro SD Card.
I followed some guides suggesting to Wipe and Format data, but nothing seems to help.
I never set up any encryption, my lock screen was set to simple swype, no pin, etc.
My SD card, when connected to the PC, works fine, all backups, ROMs etc are still there, but I can't access any of it in TWRP.
I don't care about any data or installed apps, just want to access my SD card in TWRP to run Restore from Backup or at least reinstall ROM.

Be aware TWRP backup (<3.4.0) does not include Internal Storage, you will lose all your Pictures, WhatsApp Media and Downloads. you can mount your MicroSD Card manually. adb pull /tmp/recovery.log and check the paths, then run the mount command from terminal, for example 'mount /dev/block/mmcblk1p1 /external_sd' (if your device has just mount issues but no problem with encryption you can do it for userdata partition too, see example)

Not sure if I'm doing it correctly. I connected the phone and in TWRP activated Advanced->ADB Sideload. Now from Command Prompts in Windows 10 I'm executing "adb devices" which returns "List of devices attached LGD8559819802f  sideload", so it seems the phone is recognized. Though when I try "adb pull /tmp/recovery.log" it returns "adb: error: connect failed: closed".

do not open sideload. adb is working on TWRP with root access


text:
Unable to get songs onto my phone without breaking them
All of them are in mp3 format and are perfectly playable on my PC. Here are the ways I tried.

Connect both devices via USB. File transfer is enabled, I can see the filesystem of my phone on my PC. The copying process always stops midway, even when I tried to copy one song by one song.

I took out the micro SD from my phone and put it in the PC which has an micro SD slot. Copying works?, but destination files are all broken and unplayable.

I went to the place where I originally downloaded the songs onto my PC, which hosted them as an rar archive on Google Drive. I tried to download the archive directly to my phone, but the archive disappears from my phone's filesystem after the download is done.

What is happening to my phone? It's a Asus Zenfone 5 running on Android pie. The micro SD card is about 7 years old.
Edit: I tried a few more things after posting the question initially:

Checking the filesystem of the micro SD card on Windows 10 reveals no errors.

Using FTP inbuilt on my phone, I can copy the rar archive from my PC to my phone's internal storage. After that I tried copying it to the micro SD card with a file manager on my phone. After the copying process is done, the archive is no where to be found on the micro SD card.

It seems like the problem is not my phone, but the micro SD card making the files disappear after copying the files onto it.

It would help if you can edit your post with the answers to  1. What make (Samsung/Huawei/Motorola, etc.) and model (Mi 5, Galaxy S8, Moto G7 Power),  and OS version is your device 2. What music player are you using. 3. Are you using Adoptable Storage?

How old is the sd-card? Have you performed a file-system check when it was inserted in your PC?

I did a filesystem check it shows no errors. I tried to play the songs on the SD card from my PC with Groove and WMP both of which can't pay them properly

@MorrisonChang I've added more info to the main question, and I'm not using adaptive storage (AFAIK, there's no option like that I've touched)

you can transfer files via adb. to make sure files are transfered use md5sum. DRM may also showstopper


text:
Play store apps downloading forever after factory reset
Steps before the problems :

The tablet was inactive, whitout recharging, for arround 1 year and
half.
Acidentaly pressed the keys to 'Download a custom os', and restarted the tablet during the process of download depsite the warning saying i shouldn't.
Did a factory reset trough the config option.

The problems :

All apps from playstore cant be updated or installed. When clicked on install, it will be 'installing' forever.

Cant install apk from outside playstore, i get a messsage  "There is a problem with the analisys of the package" (translated freely from my language). Tried 3 apks so far.

The time is wrong, 1h fowrward, maybe due to summertime.

solutions i tried :

For the problem 1 : Clear the cache and the data of the playstore, the download manager and gmail and forced them to stop (in a lot of diferent orders); Logged out and in the email on playstore (with diferent emails); checked for system updates (had none); checked if internal storage was fine downloading several thing from browser, all downloaded and executed normaly; Tried other apps, working pefectly(one, a store, even updated itself, but i couldnt install its apps as well; Restarted ; did another(s) factory reset; and changed the time manually.
For the problem 2 i just tried to find apk to android 4.0, and im not shure i did it ok.
For the problem 3 i changed the time manually; automatically; selected the region manually and automatcally, rebooted ; and just used the tablet for 2 days to see if would change. Did those repeatedly in various diferent orders.

Nothing worked, for any poblem. The youtube says, when i open it, that i have either the datetime wrong or a bad internet conection, even when i put the right time manually. So i think the time maybe could be causing the playstore problem also ? I dont know. Im tired.
info :

Tablet samsung p5100
Android 4.03
hardware has arround 7 years old
Touchscreen broken once, replaced in the past.
no sd card
The device might be rooted, cant tell, because cant install root checkers (it had the app supersu installed even after the factory reset. I removed it from an option inside the own app and it dosent persists factory resets anymore. Its gone)

Ps: there is no google play services installed, at least not with this name.

Solution to the problem 2 : Just install an valid apk for your current  android versions, in my case, 4.0.3
Solution to the problem 1 : Download and install (using the browser) a new playstore apk for your android version from another trusted store/site, like 'apkmirror'.


text:
How do I copy contacts from my SIM card to a Moto G8 Power?
Well there's not really more to say about my question apart from: Yes, I've looked for this feature on the Internet and on my phone.

You can copy all contacts from your SIM card using the Contacts app.
Open it, select the burger menu in the top left corner, open Settings -> Import ->  SIM card

Thanks a lot! I didn't realize the difference between the Contacts app in the Menu and the Contacts on the start screen!


text:
Help with flashing stock ROM on Nokia 3.1 (Mediatek MT6750)
I got my Nokia 3.1 in a bit of a weird situation trying to flash the stock ROM. I feel like it's a lost cause, but since I can still boot in recovery mode, there may still be a solution, I will explain in case someone can help.
It started when I tried to update from Android 8.0 to 10.0 (none of the previous OTA updates had worked and would always reboot in Oreo 8.0). This time, it didn't work and got the phone stuck in a boot loop.
The phone is still under warranty, but because I bought it overseas and there's no Nokia care centre here is New Zealand, I had no option but trying to repair it myself.
A wipe/factory reset didn't help, but after changing the active slot from B to A (using fastboot), it booted again in Oreo 8.0. Only problem is that I could no longer start a fresh Oreo 8.0 install without updating first and since all updates failed, I was stuck.
I suspect slot B is damaged or corrupt, hence the impossibility to update. To check it, I switched back the active slot to B after a factory reset, and that was not a great idea, the phone wouldn't even boot and looked hard-bricked.
But I still managed to use SP tool to download firmware, so I did that with the original Nokia 3.1 stock ROM (ES2).
However, I could not flash all files, I'm not too sure why.
I had the error message:
ERROR: STATUS_SEC_INSUFFICIENT_BUFFER
Verified boot is enabled
Please download signed image (sutinfo-verified.img) or disable verified boot
I didn't know how to do either of these, so I skipped the three problematic files: sutinfo.img, systeminfo_a.img, and cda_a.img (not sure what they do?).
It worked and un-bricked the phone, but it now boots to recovery mode only. What puzzles me is that I also no longer have access to fastboot, even when I reboot to bootloader (as if it skipped bootloader and went straight to recovery). I suspect it is because it still boots on slot B but I don't know how I can check that or change it back to slot A without fastboot access.
I tried using adb: adb shell getprop ro.boot_suffix but although it can see the device, it failed because it says device is unauthorized. I've tried all the fixes for this I found, to no avail.
So that's where I am, able to boot to recovery (but with adb unauthorized), able to flash firmware (except those files that must be signed), and unable to access fastboot.
I'm giving up hope that it's repairable, but I'd love to at least understand what happened, if someone has any idea...
Sorry for the long story...

Is the device branded by a mobile network operator (MNO)? In this case it is possible that Nokia/HMD Global has used a different signing keys and that your device is therefore locked to firmware mages provided by that MNO.

https://blog.hovatek.com/so-whats-all-this-talk-about-meditek-secure-boot-and-da-files

@Robert Thanks, the device is not branded by a MNO here.

@alecxs Thanks for the link, it explains a lot. Hovatek does not have the DA file for the Nokia 3.1, but I will try the one for Nokia 3 (MT6737) and Nokia 2.2 (MT6761) just in case.

@alexcs Regarding entering fastboot mode. I have tried both methods, it used to work but it no longer does. I think at some point, when nothing else worked, I tried for flash with "Format all + Download". This may have caused the problem as 3 files couldn't be flashed because of verified boot...

No, I didn't do a readback unfortunately. It was a bit of a last resort. I guess I should have asked for help earlier. Just to understand, does the "format all + download" formats the entire phone first or just each partition before overwriting them? Would it format partition that it cannot write on because of the verified boot?

yes it did format the entire emmc, even the secro seccfg partitions, which destroyed the availbility to use SP Flash Tool. even if you manage to flash stock ROM now there is still persist partition missing (IMEI + calibration). i recommend you to claim it under warranty because it wasn't your fault. just don't tell them anything other besides the failed OTA

if recovery still working, one thing you can try is use osm0sis' AIK to unpack recovery.img, enable adb (ro.adb.secure=0), repack recovery.img (AVBv1 signed) and try to flash. once you have root access in adb shell you can restore all partitions you have backup for (to both slots) by-passing signature check. it should even possible to root on locked bootloader and fix boot loop (doesn't work for AVBv2)

IMEI repair seems possible too https://androidmtk.com/use-sn-write-tool

Wow that's a lot of good ideas, thanks a lot. Give me a few days to try them (I'm slow as I learn most of it as I go) and I'll let you know how things work.

An update on my (non-)progress so far:

Following the advice there: https://blog.hovatek.com/so-whats-all-this-talk-about-meditek-secure-boot-and-da-files
I have tried to find different download DA files, but none of them were recognized by sp flash tool, so couldn't try to flash with them.

I have tried to readback the EMMC_BOOT partition and the EMMC_USER partition in sp flash tool, but that also failed, not sure why.

I have tried flashing using the Online Service Tool. It seems to start ok, but then encounters some error, I assume because the bootloader isn't unlocked.

I have also tried adb sideload from the recovery, and this seems to be possible. However, I have tried to use it to flash several stock firmware and
always got the error "Footer is wrong", something about needing signed files. I guess it's the AVB that is causing issue.
I couldn't find an OTA update.zip for Nokia 3.1, so coudn't try that.

I have access to the recovery log from the recovery mode
The begining goes like this:
"fail to open /sys/class/ BOOT/BOOT/boot/boot_type"
"get device_type from ro.mtk_ufs_booting for ufs devices
"platform device_type is unknown"
"platform uses default device_type emmc"
"Error: Retry fail/cache partition not found"
I don't understand all of it, but it sure doesn't look good. It's weird because I have flashed the stock ROM with sp flash tool, including preloader, kernel (lk_a), boot_a, secro.
The only partition I can't flash are sutinfo, system_a and cda_a.

All in all, it's not looking good, but I'll try a few more things next week end before I give up.

find an OTA update.zip for Nokia 3.1 (which is signed, for stock recovery)

I have tried finding an OTA update.zip, but without success, so at this stage I have given up... Thanks a lot for your help anyway.

I had the same problem as you, after looking in a lot of forums I managed to solve it, I hope it helps you.
My phone was no longer able to access the recovery, nor fastboot. After trying lots of Rom and various methods, I will explain to you which one I recovered the mobile, that is, losing the Imei, but for that there are many valid solutions.
Enter the page https://www.needrom.com/download/nokia-3-1/
You have to create a premium account to download, but they are 3USD for 1 month, download the Rom and the flashtool from that link, when it flashes put it in Firmware Upgrade mode and uncheck the preloader, sutinfo, systeminfo and cda boxes.
It worked perfectly for me and after that he let me update via OTA to Android 10.
Greetings.

can you share MTK_AllInOne_DA.bin + auth_sv5.auth + sutinfo-verified.img + boot-verified.img + recovery-verified.img for this device


text:
The phone as hotspot doesn't use its own DNS
Summary
I use my phone (Android 8.1) as access point. The qualified name of clients is resolved for other clients, but not for the phone itself.
Details
My laptop (Linux Mint 19) is set up to connect to WiFi networks using DHCP. When it does, it registers its qualified name laptop in the DNS of the access point. This is verified in several circumstances (e.g., when the laptop and other devices are connected to the WiFi network of my home DSL box, they can ping the laptop using its name).
When the laptop is connected to the phone access point, its qualified name seems to be registered as well. I test this by running host laptop 192.168.43.1 on the laptop itself, where 192.168.43.1 is the IP of the phone in the access point network. The command returns 192.168.43.44 which is the IP of the laptop (it is shown in the connection informations on the laptop).
However, apps and commands run on the phone cannot use the qualified name. Two tests:

the DAVx⁵ app cannot reach Radicale running on the laptop at http://laptop:5232/ (whereas it can at http://192.168.43.44:5232/). the log says:

  java.net.UnknownHostException: Unable to resolve host "laptop": No address associated with hostname
    at java.net.Inet6AddressImpl.lookupHostByName(Inet6AddressImpl.java:111)
    <snip>

under adb shell (phone connected in debug mode via usb), the command ping laptop returns an "unknown host" error.

Questions
Is this a bug or a "feature"? Can it be corrected without rooting the phone? (I need DAVx⁵ to be able to connect to Radicale with the same URL whatever the WiFi network used by the phone and the laptop, hence the need to use a qualified name that will be resolved to the laptop IP in any circumstance.)

That's expected behavior. Other hosts connected to phone hotspot use the phone's IP address as DNS server. DNS queries received are resopved by DNSMASQ running on the phone. But the DNS queries generated locally on the phone don't go through DNSMASQ, but use configured upstream DNS server directly (after checking hosts file). Details in How does Android OS do DNS name resolution? and How to ping a local network host by hostname

So my only option is to edit the hosts file? Is it possible without rooting the phone?

Not necessarily. There are other options. See my answer to https://android.stackexchange.com/a/219924/218526

This answer could be written thanks to Irfan Latif's comments.

Is this a bug or a "feature"? It's expected behavior (see details in the first comment).

Can it be corrected without rooting the phone? Yes. I installed Virtual Hosts, created a one-line file containing 192.168.43.44 laptop and pointed the app to it. The app is really easy to turn on/off, so I can use it only when needed.


text:
How does virtual A/B software update work?
https://source.android.com/devices/tech/ota/virtual_ab
is there any additional information or links related to the topic of software update in virtual A/B partition?
Asking for a virtual A/B update not A/B seamless update.
More info of this link details https://source.android.com/devices/tech/ota/virtual_ab

@beeshyams its for A/B  update, this is about virtual A/B https://source.android.com/devices/tech/ota/virtual_ab ending part of this document but very little is there


text:
Apply update from ADB: how to use it when you are locked out of the device
My cousin's kid has played with his Samsung A8 (2018) phone and has changed his unlock pattern. So, nobody knows the pattern the child has set.

The phone has no Google account set up
The USB debugging is not activated on device before

I have rebooted into recovery mode, and entered the option Apply update from ADB:

There is a message on recovery screen saying:

Now send the package you want to apply
to the device with adb sideload <filename> ...

I'm able to see the device by adb devices command:

According to another post, looks like it is possible to use TWRP for Samsung Galaxy A8 2018 to clear the screen lock. So, I have downloaded the following apk package:

Now I plan to install TWRP on phone by the following command and then follow the previous post:
adb sideload me.twrp.twrpapp-26.apk

Questions
Now, before doing so, I have these questions:

Is it possible to install *.apk packages by adb sideload? Is there any possibility that it would mess up the phone?
What else can I do with adb sideload to clear the screen lock?
What else can be done with adb sideload to back up the phone camera images and videos without wiping the data?

Thanks =)

What you got is the TWRP management app not the TWRP recovery, using this app you can install TWRP on a rooted device if you boot the device and start the app. 2. adb sideload is for sideloading firmware/ROM updates/full images. As far as I know you can't install APK files via sideloading at least not directly. What you should do: Perform a factory reset.

give the phone back to the childs and let keep some days, sometimes they just remember when not stressed and relaxed playing with things. in fact, that's the only option (much better chance than automatized bruteforce attack)

you can do nothing to by-pass security with sideload https://android.stackexchange.com/q/222262

read the TWRP support thread on xda. it's not even possible to decrypt, and hard enough to get a working TWRP flashed due some additional bootloader locks. furthermore it's a exynos chipset you can't use qualcomm EDL tools to dump or flash something on low level. that's a dead end

Is there a way to sideload an image that would unlock the phone? I understand that for security purposes they might want to avoid this, but it would be a really helpful loophole for those of us locked out who neglected to enable usb debugging.

Is the data on the flash memory plain or encrypted? If I were to do something crazy like this https://flashfixers.com/recover-data-dead-phone-chip-off-data-recovery/, could the data be recovered?

@PavelKomarov I think the phone is factory-reset by now! Thanks =)

@PavelKomarov I studied the link. It was interesting. Thanks :)


text:
Switch Between 2 profiles on android during device unlock
I have 2 profiles setup on my device as shown here
https://www.howtogeek.com/333484/how-to-set-up-multiple-user-profiles-on-android/
However the switching of accounts as shown here is cumbersome. Is there any app/ approach where I can enter something to unlock phone(separate pin) that will load the profiles appropriately.I sometimes hand over my phone to family and don't and switching profiles after unlocking takes too long.

This is an unsolved problem. See How to switch user profile based on password / lockscreen pattern


text:
Making a device to simulate low battery early
I have device which is used commonly by a layman kin. She does not really understand, why spares the battery if we do not wait until it goes to zero. She thinks, the device needs charge only if it was powered off due to battery exhaustion. I have no way to change her mind, but I can install or set up on her (non-rooted) Android as I want to (including adb access, if needed).
I think, maybe some app could power off her phone if battery level goes under, for example, 35% or so. Alternatively, maybe the battery load calibration could be changed to consider the actual battery level lower as it really is.
What to do?

The command to shutdown the device requires root permissions. The battery calibration is as far as I know done by the battery controller itself. You may be able to clear the data but manipulate? I don't see a different way than to educate her. May be be she can only learn it the hard way if the battery dies or the flash memory gets corrupted if the phone is not able to shut down before the power is gone.

@Robert Also education is going on, but it is more hard as sounds logical. Thanks! What if an app annoys the user by "low battery" popups? And, maybe, even in audio form?

@Robert I could also control the phone over adb, and inject touch events into. This would be a way to power it off without root. But I do not want to hack her, I only want to spare the battery :-)

Without root, it's not possible because battery status is shown across launcher & all apps. There are gimmicky apps on Play Store (search for fake battery) that merely throw up a warning but that's not going to help as the person would soon discover  //Try comparing battery to a human being while educating - being starved followed by being fully fed doesn't make an efficient person, it's eating less and much before you are very hungry or totally depleted //Likewise eating till you can't eat anymore doesn't help// see this

How deep does the battery goes (in percent) before the device shuts down? Is the device charged on "off state" or is it on/booted? If the device is charged while fully booted I may have a working idea.

@Robert To 0%. Various warnings happen before that, about low battery and offered energy spare modi, all of them are ignored.

And charging? Is the device running while charging? In that case an app pretending to be a (faked) system app could show a warning about "battery degeneration because deep discharge" may lead to battery explosion... Alternatively you may try to explain that Smartphones don't run with NiMH batteries. I assume someone educated the person you are talking about long time ago when NiMH batteries were state of the art...

@Robert It has ordinary Li battery. She does not know English, and she has no idea what is a nickel or lithium battery. She see a phone. If she wants to use it and it is powered off, and doesn't turn on for the power button, then she puts it to the charger. The warning problem could be overridden by translating the message, but I do not want to shock her, I want to spare the batteries. Bonus: this phone must be nearly completely dismantled for a battery replacement.

@Robert After it was powered off due to battery exhaustion, mostly it does not turn on for the power button. If it turns on, then it powers off very quickly again. The typical scenario is that battery exhausts, and device turns off automatically. Then it rests some hours. Then it is put to the charger, turned on, and is used. If it has luck, it remains on the charger after usage to reach 100%. Sometimes it can charge only while it is used.

Of course messages should appear it her primary language. And I don't see a reason not to shock her. Deep discharge and battery explosion are real problems if they can or can not occur on the phone is different question.


text:
Enable USB debugging through recovery mode and ADB sideload
This is a follow-up question to Apply update from ADB: how to use it when you are locked out of the device. Basically, I intend to somehow use this command to remove the lock screen:
adb sideload customROM.zip

But, the customROM.zip should be something like described here to enable USB debugging. The problem is, those steps are incomplete:

Steps to Enable USB Debugging Using Recovery Mode

Unzip the stock ROM.

Within the extracted folder, you will find the system.img well extract it too using Ext4 Unpacker

Also, extract the Update-SuperSU.v1.65.zip file.

Now open the folder where you have extracted the system.img files

Grab any .apk file from this folder and change the extension from .apk to .zip

And Copy the RSA Certificated to the Update-SuperSU.v1.65 folder (delete previous files if exist)

Also, copy the build.prop to the system folder located within Update-SuperSU.v1.65 folder

Locate the update-script file within this folder and edit it using Notepad++

You need to update the build.prop file after adding the following line at the bottom
persist.service.adb.enable=1

Next step is updating SQLite Database

Which can be done by adding the following code to the update-script file
sqlite3 /data/data/com.android.providers.settings/databases/settings.db "UPDATE global SET value=1 WHERE name='adb_enabled'"

Cheers! You have Enabled USB Debugging
Now you can install your custom or stock ROM using ADB – USB Debugging

Although the above steps seem incomplete, they look convincing that there might be a way to modify a stock ROM to enable USB debugging by:
adb sideload modified-stock-ROM-which-just-enables-USB-debugging-and-does-nothing-else.zip

Is there any better explanation than those steps?

A non-rooted stock device should not allow to install unsigned updates. As it is a Samsung device this may be a bit different (unlocking and flashing e.g. via Odin is different to most Android devices) but at least when booting first time after making your changes the device should clear all user data because of the manipulation. As I wrote in your last post the best way is to perform a factory reset.

@Robert Right, but factory reset erases all data. I just want to keep phone camera photos and videos =)

And the device PIN/pattern has been designed to protect those images from "unauthorized access" (authorized is the person who knows the PIN). I understand that this not what you want to hear. Also keep in mind that the files should be encrypted which means that even if you manage to bypass the lock screen you might still not have access to the files.

we can only tell you what is not possible https://android.stackexchange.com/q/227110

this is closest to what you want. injecting a script via flashing whole cache partition from heimdall/odin which can do modifications from stock recovery (like enable usb-debugging and authorize adb). but this is long outdated and modern samsung devices not supported https://android.stackexchange.com/q/186907

if someone knows if it is possible (or not) to exploit your device on locked bootloader then it's user elliwigy but believe me that whole stuff you found is all outdated, there is no hope in 2020. this is how i did on another ancient device https://forum.xda-developers.com/showthread.php?t=2965462

Do those steps above. However, when you get adb access on the phone, use it to rm the gesture or passwd file located in /system/system_ext/etc/passwd. This will remove the lock when you use it. Just input anything and it will let you in, which will then unencrypt your files as well.
This is the solution to the best of my knowledge, it's possible I may be incorrect but I think it will work.

I don't have the phone any longer. So, I cannot double-check your approach. Maybe someone can test it later :)


text:
How to get rid of spying app (rooted)
My android phone is installed with spyware (spying app). This can be a breach for my business leaking out passwords.
How to clean wipe android OS and freshly install Android OS again cleanly.
My system is rooted.
Phone Model : Samsung A7 2018.

Android phones are embedded device which work totally different that a regular PC. Therefore there is not "the one solution", instead it depends on your phone manufacturer and phone model. Please edit your question and add more details on your phone.

Is the 'spyware' pre installed or someone installed it??

@Aayush Hi, Someone installed it.

I am not familiar with Samsung phones, you can perform a factory reset or if you want to re-install the OS to make sure install a factory image via Odin software.

The model names of Samsung are not unique, there are three device variants for you model name:  SM-A750F/DS (EMEA); SM-A750G (Hong Kong); SM-A750FN/DS (Europe). For finding the correct firmware you have to identify your device exactly.

@Robert Can I expect the model mention somewhere on my device?? or on box?

@Robert I mean where can I find the model variant on my device/box ??

@Robert Hi, I just found my model variant online... below are the details of my Samsung A7 2018   ....     Model SM-A750F
Model name Galaxy A7 2018
Country
India (INS)
Version Android 9
Changelist 16070901
Build date Wed, 19 Jun 2019 09:53:33 +0000
Security Patch Level 2019-06-01
Product code INS
PDA A750FXXU1BSF4
CSC A750FODM1BSF4

@Robert Firmware details are clear at this link    https://www.sammobile.com/samsung/galaxy-a7-2018/firmware/SM-A750F/INS/download/A750FXXU1BSF4/278069/

@Robert Hi. Good Evening! Any help in finding the exact firmware and  working on it will be appreciated. I'm stuck not using my phone. I'm not willing to give the phone to a service center to do this job! I want to clean install everything with right process all by my myself. Thanks in advance!

You can try to download the firmware using Samloader and then install it using "Odin".

It's called "flashing the stock ROM".  Look for the firmware for your particular model (N, FD, etc.) at https://www.sammobile.com/  There are pretty good instructions at https://www.getdroidtips.com/samsung-galaxy-a7-2018-stock-firmware/
(If you still want the phone to be rooted, you'll have to root it again - the stock ROM isn't rooted, it's what you got when you first got the phone.)

Hi @Rukbat. Thanks for the comment. will one be able to get firmware directly from Samsung or Google (google being android developer)?? Sammobile.com is some unknown site which even I provided the links too. How can one get all that is required from original manufacturer or android os developer (google)?

No, but there are sites you can get the firmware from.  Just google flash stock rom and the model number of your phone.  Or check on SamMobile.


text:
How to open FTP URLs on Chrome for Android?
I can open the following link in Chrome on my PC, but my phone browser, which is also the latest version of Chrome, doesn't open it: ftp://tchdata.eili.ir (can only be accessed from Iran)
How can I open such links on my phone (Huawei P smart, if relevant)?

Chrome initially planned to depreciate support for FTP from version 81 but paused it because of COVID-19 (to help hospital staff access FTP resources) . In version 86 (currently latest on Play Store) , support to FTP has been depreciated for 1% users and by Chrome 87, it will be  depreciated  by 50% (Source).
So if you are lucky (not in the 1%), enable FTP flag by pasting chrome://flags/#enable-ftp in the address bar and launching Chrome again by pressing the prompt at bottom right.
Verified with this FTP site ftp://ftp.heanet.ie/   since link in OP can be accessed only from Iran.
If you can't access using browser, see this for other methods
How to connect an Android device to an FTP server?