text:
Page loading stops and cannot be resumed when changing tabs in Android Tor Browser
I'm trying out the Tor browser on Android 9.0 (device is not rooted). When I open a page and change tabs before the new page is fully loaded, the loading process is interrupted and cannot be resumed. Changing back to the "inactivated" tab and reloading does not work, the tab has to be closed and the page needs to be loaded from a new tab.
As usual, the Tor browser comes bundled with NoScript and HTTPS Everywhere, I'm also using the uBlock Origin extension (any opinion on this?). Background data is disabled for all apps except messengers and the max. number of background processes (developer options) is set to zero. I have tried changing the security settings as well as disabling uBO, but the problem persists... Now that I think of it, I encountered the same issue using the Brave browser on Android.
Can anyone reproduce this behaviour and tell me what's causing it? This is extremely annoying, as using Tor increases loading time with some pages, I therefore want to be able to switch to a different tab while waiting.

I have been using it occasionally on Android 10 but never faced this. Wonder if this due to internet connection?

Good question, haven't tried this on WLAN yet. But I suspect some underlying Android issue, as I encountered this behaviour with two different browsers on two completely different devices (Brave vs. Tor, Android 4.2 vs. 9.0) as well as two different mobile carriers/contracts

I have and had Brave too on 9 but never faced this

Do browser tabs in Android require background data in order to stay active?

Depends on what's on the tab - ads, scripts need more data. I would say, yes they do. Chrome restricts content refresh of background data and save power

Background basically means that the app is not being displayed on the screen, right? What about max. number of background processes in the developer options, does this have any effect?

I meant background as in app is active on screen but has multiple tabs and inactive tabs =background. If app is not active I don't think they need background data, as nothing is being refreshed. IDK about process option in developer


text:
Lock screen without using physical button Android 10
I am looking for a good way to lock the screen on my phone without using a physical button (the botton is on the edge of dying so I am preserving it for turning the phone on).
I would like to lock the phone by movement or tapping somewhere on the touch screen.
(I prefer it if this can be done without using external apps but if necessary I prefer free ones without ads.)
The f-Droid app FLock seems like it would have been ideal, but it crashes before I even have the chance to test it ().

Nova launcher can do this. You can set up gestures to lock screen and select suitable lock screen methods (see under advanced settings). I don't recall if this is available with free version (I think it should be), since I bought the pro almost immediately. Been using this launcher for many years now and this is my go - to method before I root device. Is your device rooted? Please include that in the question by [edit]ing. Rooted devices have many more options

I tried and you cannot use the gesture settings in the free version of Nova launcher. (Device is not rooted, but I might be willing to do it to solve this problem.)

So this needs paid version! Upto you to try this out or root. If you decide to root then there are some Xposed modules that make this easy but it depends on your comfort level with such things and also your device. All devices do not play the same. To be fair, there is a learning curve if you aren't familiar with such stuff

Since your home button is dying and it's much needed in the rooting process, I would suggest you go for launcher method or wait for answers

Not an answer to the question but anyone interested in the question above will probably need to know the following urgently: In order to avoid being locked out of your phone just because the physical buttons aren't working anymore you should immediately turn on USB debugging so that you have options to turn on your phone using your pc if you otherwise get locked out. See https://stackoverflow.com/a/18103158/7238575.

There's a built-in option that comes with Android 10 which allows you to lock the screen without using the bottom.
In your phone settings, go to "Accessibility" and enable "accessibility menu".
This will now put an icon on the the right side of your navigation bar. Pressing on the icon will bring up a menu, with one of the options as "lock screen". Pressing on that will lock your screen just like pressing the power button would. You also have the option to power off the phone in that same menu.
See screenshot below.

The app Lock works but a downside is that afterwards the phone cannot be unlocked using a fingerprint, only using the pattern. (Also it is not available from within other apps. So a movement activated solution would be better.)

source: Stack Exchange

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

sort: votes


text:
Issue after updating Facebook and Facebook gets update automatically
I have Realme Pro 2 (ColorOS 6 and Android 9). I updated Facebook from Play Store.
After update, the new version is Facebook 260
And the issue is:

Even I don’t this see option:

Then, I uninstalled and reinstalled Facebook and issue not resolved.
I downloaded previous version (250) and installed.
It’s okay and easy to use. Facebook 250 is working fine and I don’t want to update it. Auto-update is also OFF from Play Store. However, it gets updated automatically.
Pls let me know,
how to resolve issue with new version or how to stop it to get updates automatically?
Thank is advance.
Regards
FewL

Moreover, I did Settings & Privacy --> Settings --> Media and Contacts --> App Updates --> Auto-Update Facebook. Will that work so that Facebook will not get updated automatically till the time I do not update it manually?
And how to resolve issue after update?

If it has been updated, there's no way except to uninstall the app and manually reinstall an older version. Play Store always only installs the latest version.

As I explained, first I updated from Play Store. The updated version is 260. There is an issue with updated version. I uninstalled and downloaded previous version (250). The previous version is working fine. I disabled Auto-update from both Play Store and In-App (Settings & Privacy --> Settings --> Media and Contacts --> App Updates --> Auto-Update). However, Facebook is prompting to update the app.

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


text:
How to disable flash messages from telecom carrier?
I am having a Nokia 6.1 Plus running on Android 10.
I am facing this trouble while activating my bank on Google Pay. While the activation process, an SMS is sent. Then this flash message is shown regarding my SMS balance from the operator.

(Click to enlarge)
While this message is shown, the system gets out of context Google Pay. In return, Google Pay says this.

(Click to enlarge)
I am irritated by this, sending or receiving money is trouble.

These Class 0 messages are also called flash messages, that can be disabled by :

Calling Airtel service and requesting (personal experience)

On your device (SOURCE that lists methods for other  Indian carriers also)

Open SIM toolkit application and tap on Airtel Now! service. Now click on Start / Stop and select Stop to deactivate flash SMS completely.

In addition, you can also message STOP ANOW to 58234 to request the service deactivation.

Did you try the solutions?


text:
How to stop Stock ROM overwriting the Custom Recovery?
I was trying to flash a Custom Recovery (TWRP) on my Friend's phone (Realme 3).
It was officialy supported by TWRP and was listed on their website so I downloaded the Custom Recovery. Then I unlocked the bootloader of his phone but yes a strange thing happened there:
After it asked for pressing the volume button to be pressed it unlocked the bootloader – but after that there was option "Select boot type". It had three options: Boot to Bootloader, Boot to recovery and last Normal boot. Further there was a arrow on the bootloader option. And there were some instructions something like volume up for select and volume down to move.
But I tried every button but the arrow was stuck on the bootloader option. So I connected it to my device and used the "fastboot reboot" command to restart the device. After restarting at the realme logo it was saying "You are unlocked you cannot be trusted". But after that it booted normally and the phone was Factory Reset.
After this in the Developer options the OEM unlocking was grayed out saying Bootloader is unlocked. Ok so we were successful in unlocking the bootloader.
After that I pasted the twrp img file in the platform tools directory and put the command adb reboot bootloader and after the device was in bootloader I used the command fastboot flash recovery name.img to flash the recovery. It said sending and then writing in my terminal.
After that I used the command fastboot reboot and the the key combinations (power+volume down) for the device which used to get into recovery for that phone – but this time, instead of going into recovery, it was in the bootloader.
So again I tried fastboot reboot command and this pressing the power+volume up but the phone booted normally. So this time I tried adb reboot recovery – but it booted into stock recovery. So again I tried flashing the recovery and tried using fastboot reboot recovery but it didn't work.
And yes I know that after flashing the custom recovery the phone should first boot into the recovery but as I said neither the key combinations nor the fastboot reboot recovery command so what can I do to prevent the system from overwriting?

Anway, after flashing TWRP, disconnect from laptop and then boot into recovery. This helped me with a similar problem with MiA1

The recovery is written as part of the boot process of the main system. To disable you have to modify the system image (not sure what exactly has to be changed on your phone). A common workaround is not to flash TWRP, instead when you need it just boot it via fastboot: fastboot boot <path to TWRP image>. In that case the flash is not changed but TWRP is directly loaded via USB and started without changing the flash.

Ok @Robert and beeshyams I will try out both of them and let you know after reaching home...

it's curios that this TWRP is official but the xda support thread is closed. furthermore there are no instructions to solve this. at minimum you must disable dm-verity and delete/rename [system_root]/system/recovery-from-boot.p (if exist) This thread gives better support than the "official" https://forum.xda-developers.com/showthread.php?t=3944022

I have no idea what this was question was even about and from the answer it doesn't even follow. The answer implies you couldn't get to flash, the question implies it was overwritten when it was flashed. This should be deleted.

Ok I was able to install the TWRP Recovery using my device's stock recovery's install method... And it worked!!!!


text:
Bulk Delete Apps
On my phone (LG V30+, Android 9) I've noticed when I drag an app from my home screen into the trash, it doesn't delete the app but simply disables it. If I go into settings and find the app, I can fully remove it by pressing uninstall.
(I'm talking about apps I've downloaded, not pre-installed).
When I'm passing through airport security, I have several apps I need to actually delete completely, I can do this by going into settings for each app and choosing uninstall, but this is even more tedious than deleting from the home screen.
Is there any way to bulk delete apps that are disabled.
(ideally without installing a tool to do it, but I'm guessing no such feature exists natively)

There are tons of apps on play store that do this. Search for " bulk delete apps" and picked up the one with Highest rating (https://play.google.com/store/apps/details?id=com.hrsali.uninstaller). I didn't test any

As beeshyams wrote. You can find some such apps in my corresponding list ordered by rating together with the details on which of them are rather "tracker ridden". The one @beeshyams recommended seems to be a good choice and completely tracker-free.

@Izzy Thanks for checking they out. I just saw last update +rating

@beeshyams always a good idea to copy-paste the package name to Exodus. Easily done, too :D


text:
Huawei P30 Pro I can't set sleep mode to never
I just got my new Huawei P30 Pro and I am not able to set sleep mode to never. Maximum option available is 10 minutes. My battery mode is correct and it is set to "highest performance" so without any battery saving. I want to see my timer whole the time counting 1h and I am not able to do such an easy thing what is extremely annoying. I tried Automate or Caffeine apps but they don't work for me. My EMUI version is 10.
Please for help.

The Huawei P30 Pro has an OLED display. OLED displays have problems if the screen shows the same content for a long time in such a case it will suffer from burn-in effects. I would assume that therefore you can only have a maximum on-time before sleep of 10 minutes. The only chance I see is that in the debug menu there is sometimes an entry to keep the device awake when it is connected via USB. However activating it may severely damage your display on a long term (at least reduce the brightness when using it)!

That's ridiculous. I feel like I downgraded from my Xiaomi MI5...


text:
Desktop/homepage shortcut to send pre-built email in one click
I'm trying to set up a way to send a pre-defined gmail email to a pre-defined recipient with a single tap from the home screen. Essentially, I'm going to use emails to trigger macro events on another device, and as I will be regularly sending these emails, (sometimes multiple times per day), I do not want to have to continuously recreate them manually. I want something like Compose Email Shortcut, only I would like the recipient, subject and body to all be filled in already and for the email to be sent as soon as the shortcut is pressed. Email Yourself is the closest thing I could find to this, but that app is rather expensive for what should be a pretty basic function, and it still requires the user to press send after the shortcut is pressed.
Any help/advice appreciated...

@beeshyams Unfortunately the device that is receiving the emails does not have a SIM card. It might work if it could be done through WhatsApp or some other internet-based messaging service.

@beeshyams To be honest, I think I'd even take a free alternative to Email Yourself if that exists. I just really don't want to spend that much money on a very basic operation (autofilling fields in an email).

Automation is the preferred option. Many apps are available. I prefer using MacroDroid , since it is free (upto 5 macros and you need only one macro for your need)
and easy to learn.

Give the app all permissions it asks for and from Settings →Email settings, enter your Gmail account details.
Create a macro as shown below (use + to add triggers /actions). In the send mail action fill in details of recipient and the text of mail. In pop up action enter text that you want to be displayed when you create a widget (explained in next step). Save the macro with any name.

(click to enlarge)

From the widgets drawer of your launcher drag and drop MacroDroid Shortcut widget on top your screen. On the menu that opens up, assign it to the macro you saved.

Tap the shortcut to send the mail. I've tested and it works fine.

(click to enlarge)
You may edit the icon of widget to a custom one and add more bells and whistles by way of adding a sound action, scheduling to send mail at fixed times /days, or whatever you want ( endless possibilities)
later


text:
Unable to root Motorola G7 Power XT1955-4
I am trying to follow this tutorial https://aiomobilestuff.com/motorola-moto-g7-power-xt-1955-root-twrp-unlock-bootloader/
The command
fastboot flash recovery twrp.img

(I renamed my twrp.img to recovery.img)
gives me this error

and the command
fastboot boot twrp.img

boots my phone into twrp and it freezes it.
I am able to work again with my phone only after restart.
Is there a way so that I could root my phone?
Thanks in advance!

Does this answer your question? What is the difference between twrp-[version]-[phone].img and twrp-installer-[version]-[phone].zip?

linked tutorial is invalid/untested. this device has no recovery partition. follow the official TWRP install instructions. please note according to xda here touch screen may not work, you have to use commandline to install. for unlocking bootloader read here


text:
Will flashing "ADB enable" trigger Knox warranty bit?
I have ghost touch and I am unable to unlock my phone anymore, so I want to flash a file to enable ADB using Odin and then perform a factory reset using ADB... Will it change the KNOX fuse?
File is here: https://zfirmware.com/download-all-samsung-adb-enable-files-removing-security-frp/
Thanks.

answer: yes. unsigned modified boot.img

try to override ghost touches: unlock with physical keyboard connected via USB OTG adapter


text:
disabling sideloading APK'S via disabling the packageinstaller
i have a moto x4 running on lineage OS ver. 16 that i wanna disable installation of APK'S, so after searching online i found that deleting or disabling the packageinstaller (via debloater or adb pm commands) will disable the option of installing APK'S, the issue is that it seems that if the packageinstaller is disabled then the phone cannot boot (probably the system needs the packageinstaller) and it will tell me to make a data wipe and a factory reset, so my question is as follows is it possible to disable the packageinstaller that it should not allow installation of new apps but still be enabled so the phone can boot?, or is there another way of blocking the installation of new apps?
thanks in advance

Disabling packageinstaller app wouldn't help you at all. All it would do is make the user inaccessible the user interface they see when an app is sideloaded. Apps which have privileges to install an APK (such as Play Store or an OEM market app) can continue to use packagemanager service to install apps. Similarly, you can also install apps via command-line despite packageinstaller app disabled/removed.

thanks but both are not an issue as i don't have any play store as i use lineage OS with microG so no gapps are installed, and about command-line that is not an issue as the user is not an android tech etc. but my question is, is there a way to do what i asked to disable the installation of apps but the phone should still boot?

The PackageInstaller app is just a frontend - pm itself is the package manager. When you sideload an .apk, it's pm the one which does the job.

sorry gripoire can you explain better don't really know android so good

This question offers itself to a variety of approaches, because it seems that you are relying to an unknown extent on your user's lack of dev savvy.
A) Simplest: if your user is not an android tech, and you have no app store installed on the device, why assume that they know what an apk is and where to obtain one?
B) however, if you think that thats too simple , you can disable unknown sources and hide the setting from the user, (that should work on a reg phone, though not sure about lineage OS.)
adb shell pm uninstall -k --user 0 com.android.settings.<settingName> to disable a particular setting has been known to work on some devices, you can try it on the package manager as well, as it does not remove the apk from the phone just de-registers, though a factory reset will return the setting, and you'd have to look into preventing the user from performing factory resets.
there are many approaches that would offer a similiar level of protection.
C) Therefore, (if you think a non-dev user will figure that out,) it seems that parental control apps and/or app managers would be the most complete basic level protection.
D) you can get super deep and play around with the OS - possibly recompile the package manager app.
in summary: at the end of the day android requires pm in order to function properly. the packageinstaller app that comes preloaded with your firmware is only one of the many ways to install apks on your device because it is only a UI for a native android functionality which doesnt disappear when the package installer app is removed. to fully and irreversably disable this functionality in a way that only very experienced dev cannot circumvent is a very complicated job. However an app manager or parental control solution can usually offer near complete security from an average user.

thanks!!! so what is the factory reset setting name so i can disable it as well?

actually not sure for your device - but be advised, user can usually still launch factory reset from recovery or by secret code in the dialer, they can also force it by removing the battery during an sdcard encryption process or such. thats why i think parental control like livagent or similiar is best for you

how can i find the setting name for my device?

pull the apk from you device and dump the manifest probably - but it will only work if the setting you want is set up as a separate package. if you have root level access you can pull the apk, use 7zip or similiar to delete the activity xml - and replace the apk. this is a very "dirty" route but it may work


text:
How to remove X button on video overlay?
YouTube version 15.08.52 on Android 5.0.1 (Lollipop) is showing a X button on the video overlay user interface and it has to be tapped to hide the UI.

I searched on the internet and some posts say it's because the accessibility options "Switch Access" and "Accessibility Menu" are turned on, but in my case, the setting Switch Access is off and there is no option for Accessibility Menu.
How can I disable the option to show the X button so that the UI is hidden automatically?

Open YouTube
Click on your picture on the top-right corner
Click on settings
Click on Accessibility
Disable the thing.

Oh wow! Is this option only available on the latest release? When I searched on google I couldn't find anything related to that.


text:
How to use mobile data (hotspot) and calls at the same time?
I have a Huawei Honor 8X running Android 9 and it is pretty new - probably a year or so old. I am currently running it dual-SIM - one for my telephone number and one for mobile data. I am doing this as my telephone contract is pretty cheap, and the data contract is genuinely unlimited 4G. All phone operations default to one SIM, all data operations default to the other.
I have noticed that my phone wifi hotspot stops working when I am on an inbound or outbound telephone call. This is becoming a bit frustrating as sometimes I need to access something on the web while speaking to someone. I have done a bit of research on the web, and found that some phones prioritise voice data over internet data, but that situation may be changing on newer phones (presumably as network bandwidths generally improve).
My situation is a bit different in that I expect I have two modems (one per SIM card) and so even if this restriction still applies to phones with one card, I hope I might be exempt because I am running two.
Of course my ideal situation would be to cancel the voice contract and use data/voice on one contract. However I am happy to maintain both in the phone if I can get if that is the only way it will work. If this is considered hard to do these days - even with a modern phone - I can transfer the data card to a dongle and carry that separately.
I am in the UK.

In a single SIM situation I would suggest to enable VoLTE. Without that your phone always has to stop 4G and fall back to 3G because LTE has no voice feature. Not sure how this works in a dual-SIM scenario. BTW: Are you sure your phone has two independent modems? Usually it is just ne modem/radio (time) shared between both SIM cards.

Good thoughts @Robert, thank you. I am not sure I have two modems, no - it was an assumption based on the view that two SIMs sharing one modem has rather reduced utility. Maybe people use that just to operate two numbers, and tolerate data not working during a call.

Going by your problem I suspected that your device is Dual SIM Dual Standby, which was confirmed by GSM Arena.
What this means is that you can use only one SIM at a time be it for data or voice unlike Dual SIM Dual Active phones where you can use both SIMs simultaneously for voice /data.
Also the user manual which can be downloaded from here does not mention Dual SIM Dual Active.
So, contrary to your expectations you have only one modem and hence the behavior you experience.
Only solution is to use one SIM that has both voice and data plans since your device supports VoLTE (see user manual). Be aware that if you use both SIMs on 4G/VoLTE, only one will work on 4G and the other on 2G

Thanks, I have the same problem on Redmi Note 8T, with one SIM for CALLS and one SIM for DATA. You helped me very much, and there is description of DUAL SIM too. GSMARENA


text:
Preventing your device from vibrating whenever it gains or loses its mobile network connection
I've been using a Moto G (2nd generation) running Android 6.0 "Marshmallow".  I was playing with the settings, and changed some setting.  Now, every time the phone loses or regains cellular service — for example, when I'm in the basement, or when I enable or disable airplane mode — the phone vibrates two or three times.  The vibration is noisy and annoying.  What can I do to prevent it from happening?

I found a relevant CrackBerry.com forum post by Kathy Mansfield.  The post guided me towards a solution that works.

Open the Phone app.
Press the three-dots icon in the top-right-hand corner of the app.
Tap "Settings".
Tap "Calls".
Tap "Voicemail".
Uncheck the "Vibrate" option.

The forum poster explains:

If you have a pending notification, like a voicemail message you've not retrieved, you'll see the icon for the message. Every time your service is lost and regained, it will vibrate because of the voicemail notification. I suppose it thinks the notification is new. ...
Alternatively, you could just clear the ... voicemail message and hence the notification.


text:
Whatsapp theme suddenly turned dark
I was chatting on whatsapp, then I didn't look at my phone for 5 seconds, and when I looked back I saw that it turned dark theme with a wall paper
Why?
And now I can not get it back to previous theme, even if I select default theme or light theme etc.
How to return to previous theme? I was using default. I had not changed any setting for theme or Wallpaper
I use latest version of android (I guess) , and my phone is Samsung Galaxy S9

As suggested in comments, I looked at my phone settings and it was in dark setting. Whatsapp likely upgraded in the background to default theme so it automatically turned dark (latest version of WhatsApp does that).
To revert to light theme, from chat settings, change it to light theme. If it doesn't change, clearing cache and rebooting may help


text:
Two-factor ID and Find My Phone app
After enabling two-factor identification on my google account, I lost my android (Samsung 9) phone, so I tried to use the Find My Phone app on a friend's phone. Of course, the two-factor ID correctly prevented me from being able to use that app to find my phone.
I found my phone this time, but in the futue I would like to be able to use Find My Phone app on another device, authenticating myself with two-factor ID still enabled. I'm sure there is a way to do this, perhaps by pre-authenticating myself on Google Authenticator on my PC or a friend's phone, so in the future I can Find My Phone but others cannot. Please help! Thanks.
Siirandler

With activate 2FA you should prepare a backup code for Google: https://support.google.com/accounts/answer/1187538?&hl=en


text:
how to delete system apps from stock rom before flashing in windows
I want to remove apps from stock rom.
Tool that I used is "MTK extractor".
I unpacked system.img using MTK exractor tool, after unpacking I got "system " folder.
One youtube tutorial told me if I want to remove system apps, all I have to do is to delete apps from system/app folder.
I deleted browser.apk(built in browser), drive, google sheet, doc. And repacked the system folder.
I got system.img file again.
I flashed it using sp flash tool.
But now when I powered on my phone, it stuck on phone logo and its not powering on.
Please guide me how to remove system apps from stock rom, also I want to add some additional apps to stock rom like messenger. So how to add custom apps into stock rom

it's android 4 i guess? on new devices dm-verity prevents from booting (not the case for you) you can delete each app for it's own directly from twrp and always reboot to check if device is working or not. if offline modification is a requirement, mount system.img in linux


text:
Factory Reset without Factory Reset Protection
I've sold my old phone and perform Factory Reset to secure my data. After this the new user found that it's necessary to unlock phone with previous account.
Now, I've this user living nearby so I can perform a login of my account. But after that I want to reset my phone again to not allow him to recover my account/data.
If I perform again Factory Reset probably it will block again. How to perform a reset without enable this protection? (just for this phone and not all phone connected to this account)

remove google account before factory reset https://youtu.be/HTuoE33Kmp4


text:
How can I close my current app via a keyboard shortcut?
I have an Android phone (Cosmo Communicator) with a keyboard but without function keys. On Windows or Linux, ALT+F4 closes the application (well, window) that is focused.
Is there anything similar on Android (9.0 Pie)? I find it hard to believe this is impossible yet I was unable to google it out.

A spin on the Markus Lankeit's answer, tested on my Android TV.

Hold Alt key entire time
Press Tab key (app switcher will appear)
With arrow keys, select an app that is running
Press Del or Backspace to close the app
Repeat for other apps
You can press Esc to quit from the app switcher any time
Release Alt key

Overall, this task-killing keyboard procedure is essentially the same as on Windows 10, for example.

In Android 9:

To go home you can press the Windows key (if you have a keyboard for Windows) plus Enter

Press the Win key plus -. Android will show you all shortcuts.

Another way, if you already have plugged in your keyboard, go to "Settings" and search "Physical keyboard", there you will find configuration needed.

I do not have Windows key, unfortunately, and my keyboard is an integral part of the phone.

In my device (Redmi Note 5), we can force close the app by pressing the back button for about 3-5 seconds.

hm, does not work on my device. I am running Android 9 Pie, on Cosmo Communicator by Planet Computers. But it would not be practicle, I would like something instanteneous. Weird Android does not have that.

@sup LineageOS (a custom ROM for Android) has that feature built-in.

That does not exist from my device yet though :-( (If I understand it correctly, it needs to be adjusted for every device).

I'm on Android Pie as well, and under the keyboard settings (Language and Input), there is a physical keyboard section which lists out the shortcuts available (example).  If your keyboard doesn't come with a function key, you may need to find a mobile equivalent to AHK that can bind a certain key input or combination to invoke the meta key input.  Also note you may be able to send a keyinput event through ADB or your device's local shell terminal, which then might be made more accessible through various automation methods, some of which may have device-dependent factors.
Note: though it doesn't seem to appear on the list, I distinctly recall Alt+F4 working with a keyboard?  Will verify on current device when I get the chance.

AHK is autohotkey, a software for windows:-).
Seemns like I could use button remapper https://play.google.com/store/apps/details?id=com.irishin.buttonsremapper&hl=en  for that but I need to get root first, otherwise the action to kill current app is not available. (also not really sure if "kill current app" is what ALT+F4 does.)

Yes, that's the platform I'm most familiar with, nothing comes to mind specifically for Android but I would think it'd be strange if there wasn't an equivalent available out there somewhere.  And I don't believe root is required, but this could be dependent on your make and model's limitations and quirks.  I've seen some that work without root and some you can just grant a permission through ADB for it to work.

Also, here's an explanation on the different terms.

I got a video projector a few months back that is running Android as a base OS, to which I attached a cheap wireless generic Windows keyboard.  Projector is running some older versions of Android. Here is what works for me:
Note: Hold down the Right-Alt key the entire time:

Tab to get a list of running apps.
Pick the app to close, then Down arrow, then Space to actually close it.
Repeat for other apps.
When done, release Right-Alt key

F3 also brings up the list of current apps, but it also seems to immediately context-switch to the selected app. The same happens when you Alt-Tab and don't hold down the Alt key.

I am sure it helps somebody, but my phone unfortunately does not have a right alt key and with the left one, this does not seem to work:-(. Thanks for the suggestion though!

TLDR: keymapper sequence
Longer answer: A keymapper sequence to implement the answer given by Slider2k.
Keymapper is an app to remap your keys to perform another action, or sequence of actions. In this case I am remapping the double Volume Up press to kill the current app.
Disclaimer: I think keymapper is a great app, but it can be troublesome to get to work. Mostly to due to optimizations added by the manufactures into the firmware. Make sure to read the information given by the developer. Start by taking a look at  Don't kill my app! to access how hard this maybe to get up and running in your device.
I my case my phone's manufacturer is not that bad, but I still got into trouble with the latest version of the app and had to stick to version 2.4.4.
You will probably want to start with a version from the Play Store of F-Droid.
In case you get the app to work here is the sequence I am using:

Switch to the Key Mapper Basic Input Method, as otherwise the latter commands will not work.
Open recents. This is equivalent to pressing Alt+Tab, with the advantage that you do not need to hold the Alt key.
Then input the DPAD_LEFT key. This moves to the previous app.
The input the DPAD_RIGHT key, to move back to the original app. I had to add this detour as the recents app ignored a direct delete key.
Now input the DEL key to kill the app.
The final call to recents selects the previous app. I prefer not to be left in the app selection.
To finish-up I restore the keyboard to Gboard.

I chose to add 300 milisecond delays in between actions to make sure the sequence always worked. However I did not test smaller delays so it might be possible to reduce these timings.


text:
Android 9 pie see if device is encrypted
I am trying to figure out if my Android (Pie) is encrypted.
Per Is there a way for a user to tell if their Android device is encrypted or not?, it says my phone will be reported as phone encrypted.
However, when I go Settings --> Lock screen & security --> Encryption & credentials, here is what I can see:

One can see that:

My SD card is encrypted
Credential protection: Hardware-backed

I see no mention of phone encrypted.
Does this mean my phone's contents (not my SD card) is actually encrypted?

My Phone Specifics

LG-G710VM (aka LG G7 ThinQ for Verizon)
Android 9 (Pie)
Secure start-up is enabled

**2/24/2020 Edit**
In an answer below, @beeshyams suggested verifying encryption by following the answer to this question: How can I find out if my device uses FBE or FDE?
Using Termux I ran getprop ro.crypto.type.
It output: block, which means my device uses Full Disk Encryption.

All devices that run Android 5 and beyond (out of the box) are encrypted. That's probably why you don't see a separate status for device encryption as you see for Ext.SD.
Encryption can be Full-Disk Encryption (FDE)  or File-Based Encryption (FBE). The device is encrypted on first boot using default encryption and once the user sets up lock screen mechanism , that is used for encryption. Relevant extracts

FDE was introduced in Android 4.4 and is supported till Android 9.

Android 7.0 and higher supports file-based encryption (FBE).

For devices running Android 7.0–8.1, file-based encryption can't be used together with adoptable storage.

Devices running Android 9 and higher can use adoptable storage and file-based encryption

For new devices running Android 10 and higher, file-based encryption is required.

Your device being Android 9 with secure start up, it's most likely FBE. You can verify ro.crypto.type on Terminal Emulator and it would show file ( See How can I find out if my device uses FBE or FDE?)

Thank you @beeshyams!  Turns out my device uses FDE, see my edit to my question.  I am surprised, even with secure start-up enabled, it's not FBE.  Thank you for the answer!

@IntrastellarExplorer with "Secure start-up" turned on, your lock screen password is used for decryption. It doesn't switch between FDE/FBE. Encryption type is decided at the time of ROM development.

@IrfanLatif I purchased my ThinQ as a refurbished phone.  In that case, would ROM development have been done at the factory where the phone was made?  (I am not very familiar with Android)

@IntrastellarExplorer yes stock ROMs are developed by OEM. But for many devices it's possible to have custom ROMs which can be developed, improved and modified by any developer.

@IntrastellarExplorer I wrongly guessed it to be FBE (used likely). This should not matter to your query whether the device is encrypted. As Irfan pointed out OEMs decide

Try with getprop ro.crypto.state, if knowing whether the phone is encrypted is enough for you.

@beeshyams OP ran getprop ro.crypto.type, not getprop ro.crypto.state.

@beeshyams I noticed the answer in that link, yes. Still, OP seems to have tried the "pretty way", not your answer's "better way".


text:
Why does the official AOSP website discourage OEMs from implementing support for audio accesory mode usb c to aux adapters?
I stumbled across some documentation from the AOSP project that encourages OEMs to only support digital to analog usb c to aux jack adapters which contain their own dac to convert the digital audio coming from the phone's usb c port to analog for the aux jack. What's so bad about supporting an analog only adapter that uses the phone's existing dac to convert the digital signal to analog and simply treat it's usb c port as if it were an analog headphone jack? Audio accessory mode at least on paper seems like a complete no brainer since it means the adapters are cheaper because they don't need to have their own dac.


text:
??My samsung s9 lost the OS when i did a factory reset??? HELP MEEE
CAN SOMEONE PLEASE HELP ME WITH A WAY TO REINSTALL THE OS TO MY S9, MY PHONE USES A PROGRAMMED APP CALLED "TEAM WIN RECOVERY PROJECT" AND IT IS THE ONLY THJING THAT WORKS ON MY S9
PLEASE HELP ME
THANKS

maybe you just switched slots? who installed twrp? how exactly did you factory reset? just a hint questions with please help me are most likely ignored

TWRP is a custom recovery with many useful features, one of which is the ability to backup all partitions.  If you have a system backup you could just flash it via TWRP.  If by chance you don't you can search your specific carrier device on XDA and flash a custum rom.  Contrary to popular belief, flashing a customer rom doesn't necessarily mean rooting your device.
Another option is to download the official factory firmware from Sammobile and flash it  using a pc programe  called Odin.  You may also find official factory firmware avaliable for download from XDA links.   Smart switch is another option  you may consider looking into.  I should warn that some updates may lock your bootloader or prevent downgrade to lower OS's.
Whether you choose custom or factory always use an Md5 checker to confirm the validity of your download.


text:
wpa_supplicant issues on android phone
Disclaimer: My knowledge of android as well as the inner workings of wifi connections are exceedingly limited. Additionally, I'm new to stackoverflow, so I might just be the worst customer you had...
I'm having issues with my android phone (Fairphone 2).
For some reason, I cannot connect to any new WiFi, i.e. ones I did not connect to before. The adb logcat shows the errors:
02-24 11:33:49.215  2221  3763 E WifiConfigStore: Failed to look-up a string: WPA_EAP
02-24 11:33:49.215  2221  3763 E WifiConfigStore: Failed to look-up a string: IEEE8021X
02-24 11:33:50.221 23048  7088 E WakeLock: GCM_HB_ALARM release without a matched acquire!
02-24 11:33:50.223 23048  7088 E WakeLock: GCM_CONN_ALARM release without a matched acquire!
02-24 11:33:50.857 25094 25094 E wpa_supplicant: nl80211: Failed to open /proc/sys/net/ipv4/conf/wlan0/drop_unicast_in_l2_multicast: No such file or directory
02-24 11:33:50.857 25094 25094 E wpa_supplicant: nl80211: Failed to set IPv4 unicast in multicast filter
02-24 11:33:50.858 25094 25094 E wpa_supplicant: nl80211: Failed to open /proc/sys/net/ipv4/conf/wlan0/drop_unicast_in_l2_multicast: No such file or directory
02-24 11:33:50.858 25094 25094 E wpa_supplicant: nl80211: Failed to set IPv4 unicast in multicast filter
02-24 11:33:50.860 25094 25094 E wpa_supplicant: nl80211: Failed to open /proc/sys/net/ipv4/conf/wlan0/drop_unicast_in_l2_multicast: No such file or directory
02-24 11:33:50.860 25094 25094 E wpa_supplicant: nl80211: Failed to set IPv4 unicast in multicast filter

So I was thinking: I'm missing a file. Googling
drop_unicast_in_l2_multicast I found this webpage, so I tried to push a file of that name to the /proc/sys/net/ipv4/conf/wlan0/ folder, but I cannot do that since my phone is not rooted.
Interestingly, I found out this morning that I can connect to the open (unencrypted) wifi at my university.
My Android version is 7.1.2
I have literally no idea what is going on, so any help would be much appreciated, especially since I reset all my network settings (before I knew the issue is related to new WiFi connections in general, not just the new one I got at home), so now ALL WiFi networks are new to my phone.
Thanks a bunch in advance
Edit: Added some more of the error log

The missing drop_unicast_in_l2_multicast file should not stop you from connecting to all WiFi connections. Neither you can add that by pushing, even with root. It's a recent addition to Linux kernel. Android kernel is usually older on most of the devices currently in-use. Look for other error messages in log.

Thanks @IrfanLatif, I have added some more lines of the error message

Nothing evident from log. Just that there are some issues with authentication. May be a factory reset fixes the problem.

Thanks again. I found this bug report, which suggests that it might be a fairphone specific issue. Some people report solving the issue when setting their wifi to WPA, but that seems unwise to me. Also, it seems here that a factory reset does not help. Nonetheless, I will attempt that as well


text:
Upgraded to Android 10 - can't change MAC address
Today I upgraded to Android 10, more precisely to unofficial build of Lineage OS. My phone is Xiaomi Redmi Note 5 Pro (whyred). I am used to changing my MAC address, because our school tracks network usage. I got around it by setting my MAC to MAC of one of schools iPads. After the upgrade I can't change my MAC anymore! I turn the WiFi off as always (otherwise I would get some error like resource busy) and set the MAC using following command:
ip link set wlan0 address MACHERE

Or
busybox ifconfig wlan0 hw ether MACHERE

In both cases the MAC gets changed, but after turning the WiFi on again and connecting to  WiFi, it gets resettled back to where it was.

Any ideas what can be causing this? I have tried (so far):

multiple different kernels
rebooting

Fixed by editing wlan_mac.bin:

Why don't you add the solution to an answer with some explanation for others benefit?

Android 10 has by default MAC randomization activated: https://source.android.com/devices/tech/connect/wifi-mac-randomization

@Robert that's why it'd be interesting to know how OP got a fixed MAC address by modifying a WiFi firmware file.

@Robert The WiFi driver needs special implementation for random MACs. I was also checking that. My build has it disabled. I have permanently changed the MAC by modifying /persist/wlan_mac.bin as shown above in edit. I think that the fact I can not change my mac as I used to do before is because this ROM uses Xiaomi official WiFi driver. The fix sadly probably only works for devices with same driver/modem configuration.


text:
An Pixel XL phone shutdown by itself
My Pixel XL phone rencently always turns off by itself. Most times it turned off just after starting up, a few times it worked longer and everything looks fine. when it happend, a "phone is shuting down"(maybe not exactly these words because my phone is not in english) dialog pop up and then shut down in a few seconds.
I tried restoring it to factory image, and tried replace a new battery, and had not fix this.
I got the log using "adb logcat", here is it : full log file
Now I think its because of a hardware part, but seems not battery. I want to find out which hardware part is it from the log file, but I don't know much about the log messages, can anyone help to find some clues about what cause the auto-shutdown? Thank you very much!
John.

How do you know it is not the battery? Does the problem still occur when the charger is connected?

The log only shows that the system itself (uid 1000) has initiated a shutdown via ActivityManager and android.intent.action.ACTION_REQUEST_SHUTDOWN. There is no visible reason. May be you should retry using adb logcat -b all.

I had replaced the battery with new one before, and did not change anything.  And yes it occurs no matter the charger connected or not. Thank you for your suggestion and I will try to get more log today.

I got a new log file using "adb logcat -b all", here is it : link . Some error messages about battery appears, but currently it's the new battery in use. Can you get more details? Thanks!

If I interpret the line battery l=63 v=3913 t=72.7 h=3 st=2 c=5 chg=u correctly the h=3 means battery health status BATTERY_HEALTH_OVERHEAT. And t=72.7 should be the temperature but don't ask me if this is Celsius or Fahrenheit. This could be an explanation for the forced shutdown.

Thank you very much! So I know why it keeps shutdown itself! The temperature of my room is about 20 degrees Celsius, so looks like the phone get the value in Fahrenheit but think it's in Celsius, but it's another question. I think you completely answered my question, could you make a answer so I can accepy it? Thanks again!

Based on the provided logcat it seems like the shutdown is initiated by the healthd that manages for example the battery status:
healthd : battery l=63 v=3913 t=72.7 h=3 st=2 c=5 chg=u

This line contains two values of interest:

h=3 is the battery health value and the value 3 means BATTERY_HEALTH_OVERHEAT.
t=72.7 is the battery temperature in Celsius. This value is quite high taking it as temperature in Celsius as Android does. Hence I would assume that the battery provides the temperature in Fahrenheit but the device expects a Celsius value and therefore thinks that the battery temperature is very high. The default shutdown temperature in Android is 68°C.

What I not really understand is that all healthd message contain the h=3 value even if the temperature is lower. May be this value also reflects past temperature states.
Note: Internally Android does not directly use the temperature in Celsius, instead it uses   Centigrade (Celsius * 10).
At the moment I would recommend to do the following test: Pack your phone into a water proof box and place it for some minutes in he refrigerator (make sure you use the part that has more than 0°C, you just want to cool down the device not freeze it!).
Then get it out of the fridge and start it, and measure the run-time until it shuts down. The time should be larger than before.

Thanks for these info! I'll follow your suggestion and try more.


text:
Navigation bar and pull-down menu eerily brighter
Occasionally, my phone's display goes significantly dark. However, the navbar and the pull-down notifications menu are very brightly lit up. Any idea why?

I'm running Android 10 on Samsung M30.
P.S. Sorry about the terrible quality.
P.P.S This is not some setting, as it happens and disappears on its own. I'm trying to trace what stimulates such an eerie UI get-up.

As it currently stands, this might be a question for our photography sister side on "how to get the glare out of a reflecting object" ;) As @Robert already stated: hard to tell what you're asking.

I could see that the navigation bar is lit, but not sure where/what the pull-down menu is (Notification panel? App launcher?). However, did this happen recently/suddenly? I don't have a Samsung device, but I'd guess there's a setting inside Display about ambient light for navigation bar or similar thing?


text:
Can low battery percentage (like 10%) affect phone heating when charging?
I have LG V20 and I like to play Cyber Hunter Lite on low graphics, high resolution and high fps but I don't understand why it sometimes heat so much when playing, sometimes absolutely not, even when charging with 2A, usually no heat. I use KillApps app to kill all processes and leave only Messenger, Facebook...  only about four, reboot phone and use "Boosting" app (called Dr. Booster) to launch the game. But now it heat a lot, and can't touch the screen how it gets after 10 mins of gameplay. But my situation is exceptional. My battery percentage is only 10% now. Usually I charge and play the game when battery is above 20%. So, I wonder if low battery percentage can affect heating.  Or maybe there are other reasons. I use Lineage OS 15.1.

Yes it can. At lower battery level the charging rate is high. As level rises charging amperes decrease. Additionally this can be due to background processes. What you do with KillApps, rebooting and Dr. Booster looks pointless to me. There are better and certain ways to keep CPU usage at minimum. Cellular/WiFi signal strength and screen brightness are also major factors in heating.

Not sure if I'm right but maybe cleaning ram also helps.

Reboot doesn't clean RAM?

Yes, I read that it cleans but I remember that phone was burning my fingers after reboot, Killapps and Dr. Booster, full signal of cellular data. Now I tried on strong Wifi, cleaned ram, Killapps and it wasn't heat so much. These tries don't look very different for me.

Actually it heated up, not immediately but in 1h about.

Cleaning apps that wipe the RAM are pointless, period. The RAM is made to be filled, because your device will do nothing if it's empty. Killing apps is mostly pointless, as many of those are restarted by Android, thus wasting even more processing power. If your game is resource hungry, the game itself is the most likely cause of overheating.

@Grimoire I noticed that some apps restart. Is there any way to disable restarting? I tried an app called Task Manager by NEON TEAM but it doesn't work.

@vasik988 Back then, one would've needed root privileges or certain ROMs. I'm not certain about current Android versions.

@Grimoire The app I mentioned requires root privilegies but still doesn't work.


text:
Chinese character input is translated to emoji in WhatsApp
When inputting a Chinese character "" on WhatsApp for Android version 2.20.47, it is rendered as the emoji  instead.
My first guess is the Unicode of the Chinese character and the emoji are the same? Is there any reason behind this?
FYI: The character is typed with ChangJie, and the input code is 竹人戈一弓 or HOIMN.

The character you typed is U+E409, which is in the private use area, which means that different fonts may use it for different purposes. Private use characters should not really be relied on for general interchange. (On my machine, I get a little envelope icon.)

I'm not familiar with Chinese input methods, so I can't tell you how the input method used produced that character.

This is because WhatsApp uses Apple's emoji set, which essentially uses SoftBank mapping for backward compatibility in a Private Use Area (PUA), long before emoji was standardized in the Unicode.
The character "" (U+E409) is in the Basic Multilingual Plane's (U+E000 - U+F8FF) PUA. Since it is in the PUA, there is no standard definition for the character. While the character is supposedly rendered as , SoftBank (and Apple subsequently) apparently uses the PUA for their emoji, and U+E409 "coincidentally" renders .
Some other characters in the PUA that are rendered as emoji on WhatsApp (U+E400 - U+E40F):



Note that this is entirely WhatsApp's doing. This also affects WhatsApp Web and also WhatsApp on PC. However, other apps/OSes may render the character differently or otherwise, fails to render.


text:
Screenshots taken in the work profile are saved in the personal profile
When taking a screenshot of any app in my work profile, the picture is saved to my personal profile.
Is this the default/expected behaviour ?

I'm not sure if it is or it should be the default behavior, but it is expected behavior.
Screenshots are taken (through command-line or key combination or tile) and saved by System UI (com.android.systemui) package which is part of stock Android. When deciding where to save the screenshot file, the path is decided (using getExternalStoragePublicDirectory API up to Android 9 or MediaStore on Android 10+) based on the current User_ID (not UID), which is 0 for device owner (personal profile) and 10, 11, 12 .... for secondary users/profiles.
Since profiles are not completely isolated users but associated to a parent user, separate instances of only essential apps and packages are run under new User_ID. All display related things e.g. notifications, lock screen, status bar etc. in secondary profile are handled by primary user's System UI process which is running under User_ID 0 e.g. with UID 10500. So the screenshot is saved to primary profile's storage i.e. /storage/emulated/0/Pictures/Screenshots/.
However Multiple Users are more isolated than profiles and unlike latter, two users cannot share user interface. When you create and switch to a new user (not enabled on all ROMs by OEMs/developers), a separate instance of System UI app is run e.g. with UID 1010500. So the new user has a separate lock screen and doesn't share notifications with primary user. Likewise a screenshot is saved to /storage/emulated/10/Pictures/Screenshots/.


text:
How does one restore data to phone from Google drive?
I backup my data from my Android phone to Google Drive. I then performed a full factory reset. I was given the option to exchange data with another phone, but not restore from Google Drive.
When I go to Google Drive from the app, I'm able to see the backup. I can view the files, but the only option I'm given is to delete them.
Is there something I'm missing? Why can't you restore incrementally from Google Drive? And how do I get my data back without having to do another factory restore? Finally, why wasn't I given that option when I perform the factory restore?

That's one of the reasons this type of backup is what I discourage from (it's not a backup if I cannot chose when and what to restore – but I'm preaching the choir here I guess). If you don't mind the command line (adb shell), you might be able to trigger things via bmgr (the "backup manager"). I've never played with it so I cannot give detailed instructions, hence just this comment as pointer. See here for more – and please let us know the outcome!

It doesn't appear that this will work with the existing backup. So is what I have on Google Drive useless?

No idea; I've stopped using Google stuff years ago, my devices run LineageOS w/o GApps.

you could maybe download to pc and analyze file format, maybe it can unpacked and restored manually

Here's a real-life case on someone who'd gotten Google Backup to restore indirectly without root: screenshot
As I recall, a manual trigger for the G Backup restore function was planned for the Pixel series, but this was over a year ago that I'd read about that so I'm not sure what became of that; at that time, an ADB command existed to trigger such behavior, but I'm unsure what the prerequisites and/or limitations are.
My post here also briefly touches on G Backup and other methods I'd explored to solve my own issue with restoring a backup file's data.  Note that there is versioning requirement for the standard restoration method(s) to work, i.e., you can only restore onto a device running the same or higher  of Android (if even then).
Finally, here is a guide I wrote (and fixes) for an Android game, but the same functionality can be applied to more general usages as well.


text:
command line language for Android tablet (wget equivalent)
I am a Linux enthusiast and probable expert, and using it since 1993 on the command line (today with zsh) (and Unix since 1987, SunOS3.2).
I personally have a Huawei tablet, details here. With an SD card.
I also have a Logitech Bluetooth keyboard case for that tablet.
I need to be able to read some PDF documents on the tablet without a working internet connection. (at my work at CEA/LIST - a quite bureaucratic organization since indirectly related to French nuclear warheads, I have a powerful Dell workstation with root access & Ethernet connection to the Internet under Debian/Unstable - so sometimes Xorg does not work properly -, but no access to the corporate Wifi; for the clips-rule-gcc project I prefer to read the CLIPS documentation on my BYOD tablet).
If my tablet was good genuine Linux Debian system, I would just wget http://clipsrules.sourceforge.net/documentation/v640/bpg.pdf when Internet is available, and later evince bpg.pdf when it is not, taking advantage of zsh auto completion facilities.
What are the equivalent on Android 8 ?
My AppStore is google, and I was not yet able to root my tablet. Dreaming of that every day.

Depending on your device/ROM, it ships with either toolbox, toybox or busybox. At least the latter usually ships with wget, which you then could use either directly (wget ..) or indirectly (busybox wget ..); you can try the same with toolbox if available, but that and toybox usually don't have wget. Last resort would be installing a busybox app from your favorite store. As for PDF readers, there are plenty.

I am veryu unfamiliar with Android. busybox don't work without root access. rootchecker costs me 3.5€. Can I avoid that?

@BasileStarynkevitch busybox or any static built binaries work perfectly on non-rooted Android. Use with adb shell or any terminal emulator app. Termux is a good one.

adb push busybox /data/local/tmp

i don't fully understand the question is about cmd line or app recommendation, why don't you just install any pdf viewer (like OfficeSuite) you can even open pdf from cmd line if this is requirement

Did you tried Termux?
The terminal emulator for android, this does not require any root access either.

Edit: to install wget type pkg install wget and press enter.
For pdf viewer use native android one such as Mu Pdf or, Google pdf viewer
Once installed you can try xdg-open filename.pdf
It will give you a list of the compatible app to open the file or else you can open the pdf viewer app to browse files of your choice.

Thanks. apt install evince fails after installing package x11-repo

@BasileStarynkevitch use a commandline PDF reader or GUI Android app. X-server is not native to Android, so is always troublesome. You need to install additional XServer or VNC app and configure x-11 to work with them.

But which one? I never used Android before this year

@BasileStarynkevitch See my link above (comment on your question). I use MuPDF and am quite happy with it. // digiwizkid: could you please [edit] your answer and include the details on wget etc? Just installing Termux doesn't solve the problem. I guess it either comes with wget (in that case say so), or one must apt install it (then that should be pointed out). While on it, maybe integrate the details from your comment as well?

@BasileStarynkevitch I have edited my answer, please check. If this answers your question please accept it. Thanks

the android cmd line language is MirBSD Korn Shell mksh and default core utilities are FreeBSD or toybox (and few android specific toolbox) applets
there is no dpkg or apt equivalent the closest is android package manager (commands am or pm)
default console is android debug bridge (like ssh) you need to enable usb-debugging in developer settings, connect to pc and install package android-tools-adb then you can start adb shell and authorize the ~/. android RSA-key by simply accept confirmation dialog on tablet

am start -a android.intent.action.VIEW -d file://bpg.pdf


text:
How to patch and sign android bootloader image to enable "volume_up" button?
Had trouble with it for a long time because manufacturer disabled the button to unlock the rooting functionality.

Bootloaders binaries are signed with OEM's private key. You can't sign them. And they are closed-source and highly vendor-specific. There is no general way to patch them.

I managed to find an answer to the continuation of my question. Which technically removes any reason for this question. Should I answer this question by it or create a new one?

It'd be better if you post the answer for other's benefit.

@IrfanLatif Is it really practical to repost info from xda-developers ? It's the post about suboot.sh which works with mtk-su and magiskinit on mtk devices

You can provide a brief description with link so that answer is not useless if link is dead.

fastboot oem key 8 # vol up
fastboot oem key 2 # vol down fastboot oem key 5 # power

@alecxs
fastboot oem key 8 returns
FAILED (remote: 'argument size is wrong')

seems working for HTC Leo (got it from the mtk-su thread)

I live in the U.S. and what was once the land of the free is now the land of the locked bootloader.  Good luck
https://www.geektrouble.info/explore/android/view/218873
"OEMs/SoC vendors implement a Chain of Trust which must have a hardware-backed root of trust - a cryptographic key. On boot every software component verifies the integrity of the next component before loading it in memory. This chain of trust starts with BootROM (the very first executable code which runs on Power ON) and ends at /system and /vendor partitions. Everything in between - bootloaders, Device Tree, Linux kernel and Android OS code - is verified to be unaltered."

That's my answer to this question: https://android.stackexchange.com/a/218886/218526


text:
What is "GPUwatch Interceptor app"
I was going through my settings today and I clicked on privacy then checked my special access and noticed something I've never seen before. An app called watch GPU interceptor it had full access permissions with no description. I turned it off went back to the main menu a few minutes later I went back to special access and it was still there and set to on, full access. I searched everywhere I could on my phone went through apps permissions I couldn't find it as an app. I found GPU watch which was in developer options, I turned off developer options then went back to special access and had to turn off ""GPU watch Interceptor "" again. I cannot find that exact phrase in Google search. I'd like to know if this was something that I turned on in developer options or if it was some sort of Hack / malware.
I'm using a Samsung S10 Plus, with Android 10 on Verizon and home Wi-Fi
I have added a screen capture of what I saw
Thank you

No, It doesn't a malware.
GPUWatch aids developers in their monitoring and measurement of performance between Vulkan and OpenGL ES. It’s now packed with new features, such as overlaid measurement results and real-time information on-screen – all made possible without separate installation or PC connection. Samsung NewsRoom

How is showed in the smartphone screen :

image retired from link GDC19

For to deepen in GPUWatch I recommend to you two Youtube videos:
GDC19:  A talk of HyoKeun Lee addressing about why use that tool.
GDC18:  HyoKeun again, showing how to use GPUWatch.


text:
What android icon app is this? Please advise
not sure what this icon is but any help would be greatly appreciated.

This is the icon of Google Sheet file. It is visible in Google Drive for Google Sheet files. Google Sheet is an alternative to Microsoft Excel.

you are awesome! thanks so much!

@LoR4106 I'm glad it helped
Don't forget to mark it as correct answer ✔


text:
Unable to transfer files on android 8.0 TV box to the USB
Unable to transfer files on android 8.0 TV box to the USB.
I have tried many file transfer apps but none will transfer to my USB even though it shows my USB connection and any files that are on the USB. Can anyone help?

Have you tried TotalCommander?  Its possible that the USB drive is mounted as read-only.  In TotalCommander, If you copy to the USB drive and the USB drive is mounted as read-only: TotalCommander will automatically ask if you want to remount the drive as read-write, which is what you want.  Say 'Yes', then it copies whatever files you want to your USB.

Hi thanks for your help, total commander worked, it transferred the file without asking to remount the drive as read-write. No other programming would let me transfer files. Thanks again Jeff Luyet.


text:
Images received though social media end up in the camera-app Gallery
Lately, in the Gallery app associated with the camera app of my Samsung phone (Android 8.0.0), I can see not only past pictures I've taken with the phone camera, but also pictures that people are sending me through whatsapp, viber and other messenger/social media apps.
I didn't see any options in the Gallery app itself to have those land not in the same place as my camera-taken pictures.
Is there any way to keep the two categories of pictures (whatsapp attachments; and camera pictures) separated?

Which gallery that is (exact package name)? Why don't you try some other gallery app? There are many free, open-source, feature-rich galleries available.

It's the stock Gallery that one gets taken to when one taps on the circular icon denoting the last-taken picture, in the camera app. I'd prefer to keep using this Gallery app due to its ease of access (double-press home button to fire up the camera app)


text:
How to verify sideloaded APKs?
I have sideloaded APKs, which are not available on sites like APK Mirror or APK Pure, from Google Play via the Evozi APK downloading service. It is an online banking app, so I want to verify it. How can this be done? I get checksums by uploading the files to Virus Total:

How can I get the checksums of the authentic APKs?
NOTE: I do not have a Google account.


text:
Android boot.img installing BusyBox with Dropbear
I have installed TWRP on my device, extracted boot.img.
Initially I just wanted to build Dropbear for Android and make it run from boot.img.
I don't need any app to have root access.
What I would like is to have Dropbear running root and be able to SSH into it having root access.
I'm not experienced with BusyBox. I used a little bit of OpenWrt with BusyBox 1.28, but seriously don't know it much.
What I need is to have root SSH access to be able to configure some things. Be able to do some configuration with Ansible Playbooks for the phone would be nice addition.
I'd like to be able install certain program packages, the similar way I did in Openwrt I recently installed cURL package. I need to write some scripts which will be executed as jobs, something like cronjobs.
So the question is, do I need BusyBox for that or just build Dropbear?
It seems BusyBox would be very nice thing in my case.

For scheduled jobs run busybox crond. On Android 10+ init services can be run as scheduled jobs with restart_period option, so you don't need a third party tool. // If you need remote shell adb in WiFi mode may help but doesn't fulfill my needs. So I run a full OpenSSH server: How to run SSH/SFTP server for multiple user logins with password authentication on Android?

@IrfanLatif I see you use busybox, have you just downloaded binary or build it yourself and run it on your android or you're using Magisk Core Mode Only which has busybox? Seems there's no need for me to use Magisk.

I have used different busybox builds but ATM I'm using my own (you can find it here). It's somewhat limited because for many tools I use static built binaries e.g. coreutils, util-linux etc.


text:
Google Translator does not appear automatically anymore
When I was using WhatsApp and chatting with my foreign friends, when I copied their text, the Google Translator was automatically appearing.
But now, after the Android update, it doesn't happen. I tried settings in the translator app but there is nothing to enable that.
Settings > Tap to translate > Enable
did not work.
How can I make the translator app button automatically appear whenever I copy a foreign language text?

Have you tried clear data and followed the procedure again?

Just in case it's related, could you also mention the phone model and the Android version?


text:
Unable to delete .apk file
I downloaded a ROM file on my Google Pixel 3a XL and it left behind an APK file with the name of the game.

I am now unable to delete the file. When I try to, it just has a pop-up saying 'couldn't delete 1 file'.
If someone could please advise as I'm worried about having this file.

You are on Android 10?

You could try rebooting your phone and deleting the file.  It's possible that a running app or service has that file handle open and won't let you delete it for that reason.
It's also possible that maybe the file is already deleted, it's just your app that you're using to view the file that needs to be refreshed.  It can't delete a file that doesn't exist.
You could also use TotalCommander to delete the file.
If that doesn't work, you can always plug your phone up to your computer and use ADB.
adb shell rm "/storage/emulated/0/Download/Mario Party 7.apk"

(replace /storage/emulated/0/Download with actual file path)


text:
Switch from micro USB to USB c, buy adapters or new cables?
Firt of I'm not a 100% sure this is the right site to ask this on but here we go.
So I will have to buy a new phone in the near future. With this I'll most likely get one with USB c instead of now micro USB.
I have quite a few cables for recharging (1-3 at home, at work, and one for my powerbank) all of those are micro USB and still work fine, some of them are long cables so they weren't that cheap.
My question now is: is there any downside to buying adapters and sticking them on my already owned cables or should I have replace them? (clearly not all of them as I still have other stuff that charges with micro USB)

Personally I prefer cables without adapter. Especially when it comes to charging the adapter may reduce the maximum charging power (because it works like a resistor).
If you use an adapter I would strongly recommend to use an short adapter cable, not a small fixed adapter with a plug and a connector in a small case: The adapter without cable effectively extends the length of the plug and therefore also the force you apply onto the USB port on the phone's mainboard (because of the leverage effect). Hence using an adapter can decrease the lifetime of the USB-port.
Therefore I would replace the one or two most used cables for now. Others can still be used with adapter. In some months you know what you prefer and if it makes sense to buy more USB-C cables.


text:
Getting started with emulator
I'm sorry that this is almost certainly one of those "read the docs" questions, but I've been trying to do so for a while now, and my head is spinning. I suspect what I want is impossible, but would appreciate if someone can confirm/deny/point me in the right direction before I tear any more hair out.
I want to start to tinker with Android and determine whether I want to learn this environment or not. I have installed Android Studio on my Ubuntu Linux 18.04 primary development machine which has 32G RAM and an I7-4790 processor. However, I also have VirtualBox running and it's not an option to shut that down. Consequently, the emulator refuses to start.
My investigations then came across "genymotion", but their website seems to indicate that even a single dev license is over a hundred bucks a year. Am I right about this, or are they merely hiding a community edition somewhere? I'm not willing to pay for the tools at this stage of discovery.
So, my specific question: is there a zero money emulator that I can use on Linux, concurrently with VirtualBox?
EDIT: I took advantage of the need to do some upgrades and took VirtualBox  down for ten minutes last night. I succeeded in proving that the emulator and the AndroingStudio installation work perfectly under these conditions.

I would update your question with which CPU your Ubuntu box is running and what happened when you tried to install an Android x86 flavor that supports VirtualBox.

Added CPU type, but I don't know what you mean by "tried to install ..." I took what was offered by the AVD manager. It only appears to offer variations of Android hardware and Android OS revisions. This sounds like there's more for me to know, and that's exactly what I'm hoping to find out! :)

So you didn't find: https://www.android-x86.org/documentation/virtualbox.html and https://osdn.net/projects/android-x86/releases OR are you only looking for official sources in which case only HAXM is available. You might be able to run older ARM system images (Android 7 and lower) without HAXM but they run really slow (QEMU based).

Didn't find anything other than Android Studio ;) I'm not snobbish about what I run as long as it's tolerably stable! So, I suspect that the x86 thing that I was just bumping into (comments I just made on Bo Lawson's answer) might be my path of least resistance. Thanks!

Yes, in fact Android absolu has an emulator called quemo  There are a couple of  beautiful things about quemo. For one you just need to use your
Linux machine to Git clone it in. Second, it is from the Android Google source code and you do not need to download Android Studio.

Interesting. When I poked around to find out what was going on when the emulator launched by Android Studio was failing, I found this command line in a ps output:
Android/Sdk/emulator/qemu/linux-x86_64/qemu-system-6_64 -netdelay none -netspeed full -avd Nexus_6_API_27
But that's the emulator that was failing to run. Is this the one you're describing, or different (I notice you spelled "quemo", but the git repo, and this command are both spelled "qemu").

Oh, and I added an edit. The emulator does work when VirtualBox is out of the picture.

Hmm, are you saying I should be running qemu as a VM inside VirtualBox? That seems to be what this post is driving towards: https://www.howtogeek.com/164570/how-to-install-android-in-virtualbox/


text:
File Sizes (including hidden files) don't sum up to total data usage
I recently noticed that my Galaxy S9 was running low on space. While using the 'My Files' app that comes with the phone to do some spring cleaning, I noticed that my Internal Storage shows a usage of about 47GB.
However, something doesn't add up. I open that folder, turn on display of hidden files, and select EVERYTHING that is listed. The result is only 13.72GB!?!?!?!?!!! This is WAY WAY off. I have a huge amount of space getting used (over 30GB) and no idea what is actually using it, nor how to clear it out.
I have tried using cache cleaners, like Norton Clean, but those only found about 1GB of residual files, etc. I have also tried restarting the phone, but this doesn't help either... Other than a factor default reset, I can't think of anything else to try. Can anyone help me figure out what is going on?

See my answer to How disk space is used on Android device?

Hmm, it looks like you needed to gain root access for a lot of that... is there anyway to find / clean out the junk without rooting my phone? I ask because if I root my phone I may not be able to access internet at work which has a policy of denying access to rooted phones.

Clean /sdcard AMAP. Clear app caches or complete data. Uninstall unnecessary apps. Or perform a complete factory reset.


text:
Where does Android acquire the weather (temperature) that it displays on the main screen?
I am building an app that will need several weather parameters. If they are already available somewhere internally, I would like to access them. If not, please identify the web service(s) that Android is using, if possible.
Specifically I am seeking temperature, pressure, and relative humidity.
Thank you.

Weather apps are manufacturer specific. Hence your question can't be answered as it it unclear of which weather app you are talking about. In any way there are dozen of weather data provider. Usually those provider require a registration and some times you have to pay for the data. The only alternative are community based weather data provider such as wunderground.com or openweathermap.org.

Android (AOSP) doesn't show temperature, apps do. So it's up to the developers: https://stackoverflow.com/q/15425283/9165920

@Robert My Pixel 2XL displays the outdoor temperature on the factory locked screen as well as the main unlocked screen, so that is why I attribute that to the OS rather than an app.

@Kirk Pixel devices don't run Android (AOSP). Hence it has been added by Google specific for the device. Only Android One devices run a nearly plain Android. In any way you are usually not allowed to use the same API. If you want to know where it gets the data redirect the traffic through a decrypting HTTP(S) proxy and prepare your device to accept the proxy certificate.

Google (including Nexus and Pixel devices) uses Weather.com. It's the same as querying "weather" on Google search (there's "More on weather.com" on the bottom).


text:
Password protect adb
Looking for an option to password protect adb so I can enable it all the time and accept all connections.
In the event if I break my phone's screen and I need to pull my files out this would really be helpful.

adb supports RSA key authentication (if configured) which is far stronger than a password: https://android.stackexchange.com/a/219320/218526

You don't need to "acept all connections". Just make sure to backup the adb authentication keys from your PC once you have accepted them on device. Then nothing can go wrong if you ever need adb access.

... nothing except https://android.stackexchange.com/q/226666


text:
prevent people to see that I use whatsapp
When Alice adds Bob's number to their Android contact list, they can infer whether Bob is using WhatsApp by looking at their WhatsApp contact list. Only if Bob uses WA, they will show up there. How can B disclose their phone number to A while hiding the fact that they use WA?

Maybe blocking Alice would work? I didn't try it so you'll have to test it yourself. The other option might be to have a different number for WhatsApp or to give out to people

Depending on the capability of WhatsApp and Android system, what you want to do might be impossible to do with the official WhatsApp. I don't know if modded (unofficial) WhatsApp might help though.


text:
How can I get gmail notifications to start working on a Samsung Galaxy S10+?
Got a new samsung s10 plus phone and I dont see Gmail notifications. Notifications dont show up anywhere irrespective of being on wifi or phone data.
Things I have done so far :

Battery optimisation turned off for Gmail
Adaptive battery - cycled between all available modes.
Notifications turned on for Gmail (Settings -> Notifications)
All gmail app notifications turned on within the app (Gmail -> Settings -> Notifications)
"special access" > optimize battery usage > turn of the gmail app (which I believe is the battery optimisation option anyway)
S10 settings > Apps > GMail > Mobile Data and enabled "Allow background data usage" and "Allow app while data saver is on"

The phone has the latest software and is up to date. I have followed the discussions on the top 5 google results of "gmail notifications not working on S10 plus" and haven't been able to find a solution. I am hoping I can find some help here.

Did you try clearing data of the app? (Settings > apps > gmail > clear data)

@aBochur - That did it !!! Thank you

I had the same problem with my new s10, and the clear data didn't work.
I had to dig in the settings to find it out that when turning the power save mode, it disables the auto syncronization.
You can manually turn sync back in the setting menu when you swipe down from the top. and preserve the power save mode.
Such easy thing but it left me several days without notifications.
Hopefully helps, and saves someone else's time.


text:
How do you disable Ambient mode?
I disabled Google Assistant on my phone* but Google's Ambient mode kept showing up when my phone was on charge.
I didn't want Ambient mode (it wasted power and blocked me from accessing the lock screen); how do I make it go back to pre-Assistant behaviour?
Note: I have turned off Google Assistant; this had no effect.

Mi2S with Mokee kernel (Android 8.1.0)

I have successfully disabled Ambient mode.
... by turning on Google Assistant and then turning off all the options (including Ambient mode).
The Google Assistant options can be reached (on my phone at least) by traversing: Settings | Google | Account Services | Search, Assistant & Voice | Google Assistant | Assistant (tab) | Assistant Devices | {choose your device}.
I'd like to see Assistant off -> Ambient off, but for now it's a solution...


text:
How to fix mount errors when trying to mount the raw image that converted from android sparse image?
I have sparse.img image with the following properties:
$ file sparse.img
sparse.img: Android sparse image, version: 1.0, Total of 2512896 4096-byte output blocks in 60 input chunks.

I want to see its contents so

I have converted it into raw image.
Created a new directory
Trying to mount the raw image on to the directory

using the following commands:
$ simg2img sparse.img sparse_raw.img
$ mkdir raw
$ sudo mount -t ext4 -o loop sparse_raw.img raw

First two commands run fine and I can see sparse_raw.img generated of size larger than sparse.img.
Last command failed with an error:

wrong fs type, bad option, bad superblock on /dev/loop27, missing codepage or helper program, or other error.

I think that may be the sparse_raw.img is not an ext4 image but how can I sure about it?
I have tried to mount it as

ext2, ext3 or without -t
without -o loop
but nothing works.

Please suggest a way to fix it.

Does this answer your question? How do I find what type of file system is of an attached USB or SD card?

file sparse_raw.img prints data. hexdump -C -n1040 sparse_raw.img prints 78 ba 2a 63 7a 05 50 ed ... so it doesn't match with 10.20.f5.f2 or 53.ef.

@IrfanLatif The image is not mounted on any android system but it is available under file explorer of Ubuntu.

@VatishSharma I didn't say you need to mount the filesystem to see what filesystem it is. Checking filesystem is same irrespective of if it's a block device or a loop file; on Android or on Linux distro. Output of file and hexdump shows that it's not a filesystem. So mounting will definitely fail. Problem is with your sparse.img or simg2img, not with mounting.

I have other sparse.imgs and they are working fine with simg2img and mount command but the one mentioned in the question and two more are not working. Any suggestions on how can I determine the problem?

@VatishSharma who created the sparse.img? Ask them what tool they used for sparseness and compression, and what filesystem it contains. It can be ext4 or rarely f2fs (on /system or /vendor). Or EROFS in case of Huawei. Some vendors also experimented with SquashFS. Also use a different simg2img binary. Better build from latest source.

try this older build from fguy https://forum.xda-developers.com/showthread.php?t=1054836&page=5

sgs2toext4.jar this worked instead of simg2img. Thank you guys for your help :)

The file system might not be in the beginning of the raw partition image.
First you need to convert the image from sparse to raw, using either simg2img or sparse_img_to_ext4.py.
Then, you need to find the beginning of the actual partition, binwalk is my favorite tool for that:
$ binwalk super.raw.img

DECIMAL       HEXADECIMAL     DESCRIPTION
--------------------------------------------------------------------------------
1048576       0x100000        Linux EXT filesystem, rev 3.0, ext2 filesystem data, UUID=8f83745e-c212-5aab-a776-4aeed9fad9fa, volume name "/"
[...many many irrlevant hits...]

Now you can mount the file system using the first offset from the binwalk output:
sudo mount super.raw.img -t ext4 -o ro,loop,offset=0x100000 /media/super/

The ext4 feature (400) is the new metadata_csum feature. If this feature is enabled and old tools are used to mount the filesystem they will only be able to mount read-only.
Try to mount it read-only:
$ sudo mount -t ext4 -o ro system.img.raw ~/mnt


text:
How to enable a disabled app in Samsung
Phone: Samsung Galaxy S9, Android 10, OneUI2.0
After updating my OS last month, the "Enable" button disappears from App info panel(Settings | Apps | (app) | Enable, said How to enable a disabled app). and "auto disable unused app" setting is not available, too.
If the app is installed by play store, I can re-enable it in play store app. If not, how to enable?
And I tried pm enable ... cmd in adb, but got

Security exception: Shell cannot change component state for .../null to 1


text:
How GBWhatsApp works?
I came across an application named GBWhatsApp. It is developed by some unknown people and there are many sites from where you can download the APK. It's not officially on the Play Store for some reason.
It was a big surprise to me to see that using this app, I can actually chat with the people who are using the official WhatsApp application.
I did some googling and found out that it is a modded app of the original WhatsApp application. It is built on top of the original application. This means some people/developers/engineers decompiled the original APK and inserted their code and published it with another name.
My questions are,

Is WhatsApp APK so much less secure that some engineers were able to decompile its Java code successfully? And they provided a lot of new features that are not there in the original app?

I know APK can be decompiled, but if the original developer team has obfuscated the code (ProGuard, etc), then it's almost impossible to reverse engineer the Java code. How did this happen?

Also, if it is not a modded app, it means they build their own app which is similar to WhatsApp, then how they are able to send messages to the official app?

nothing useful but maybe a little more information https://forum.xda-developers.com/android/apps-games/whatsapp-gbwhatsapp-devices-t3518808

It's not a matter of "security" - any app can be decompiled, modified and reassembled. Moreover, obfuscation isn't a magic wand, as it's only a deterrent to rookie "hackers": if someone is persistent enough, they can eventually interpret what the different parts of a program actually do, edit them and get their own version to work. GBWhatsApp is an example.


text:
Insufficent rights for npm install in Termux on Android
I'm trying to install a Node.js module in a folder, for example, /data/data/com.termux/files/home/storage/shared/documents/projects/code/js/test-npm, from Termux on rooted Android 6 running npm install. Installation starts, but never succeeds, throwing errors and warnings like npm ERR! cb() never called! and WARN tar EPERM: operation not permitted, futime.
Which permissions should I grant to npm and how?
Update 1: tried running npm install in /storage/emulated/0/Documents/projects/code/js/test-npm, got the same errors. Termux has Storage access permission in Android installed apps manager.

Related: Unable to install express ( of node.js) in Android termux using sdcard0 as directory

WARN tar EPERM: operation not permitted, futime indicates that futime syscall (used to change file last access and modification times) fails with error: EPERM. From utime manpage 1:

EPERM  ... the caller's effective UID does not match the owner of the file ...

That seems to be the reason of failure. You are using path: /data/data/com.termux/files/home/storage/shared/ which is actually /sdcard/ 2 (symlink to /storage/emulated/0/). It's not an actual filesystem but an emulated 3 view of underlying filesystem (ext4 or f2fs). It has fixed permissions and doesn't support many features of Linux filesystems including symlinks and ioctls like FS_IOC_FIEMAP 4.
Due to fixed permissions all directories and files in /sdcard/ are always owned by user root (UID 0). So while trying to change file's timestamp, Operation not permitted is returned. touch command however uses utimensat 5 which has different permissions requirements.
So to avoid this problem, you should not use emulated filesystem. Termux $HOME directory is on ext4 or f2fs, so it's a good place to save files. Use e.g. /data/data/com.termux/files/home/npm-test directory.
From comments:

But is it possible to somehow create a link inside $HOME to another location, which will grant all the rights that Termux has for $HOME for all the subfolders of this distant location?

No it's not possible on non-rooted phone. Apps can write only to their private directories in internal storage (which is /data/data/com.termux for Termux) and in shared storage (/sdcard/Android/data/com.termux). Apps with Storage permission granted can read and write to whole /sdcard/. There is no other place on device where apps can save files 6. With SELinux disabled or permissive, it's possible to write to a sub-directory created (with adb shell) in /data/local/tmp, but it's not intended use of this directory.

LINKS:
1 utime manpage
2 How do I access $HOME/storage outside of Termux (with a file explorer)?
3 What is /storage/emulated/0/?
4 How can I make a symlink inside /storage/emulated/0?
5 How to change the modified date of a file without root?
6 Where Android apps store data?


text:
What are these carrier configuration settings and which Android service handles them?
I signed a new mobile contract and received a carrier configuration message, but it seems that the settings were not updated properly. Up- and download is way too slow (typical 3G speeds) despite "4G" being displayed in the status bar. Which Android service is responsible for automatically updating carrier configuration settings and which settings are relevant for 4G connectivity?
Device, OS: Samsung Galaxy A40 (SM-A405FN) with Android 9.0
Carrier: Telefónica
Data plan: 3 GB LTE
These are the APN settings (3rd column) as specified by the carrier:

Mobile Data:

APN
Username
Password
MCC
MNC
Authentication Type

MMS:

APN
Username
Password
MMSC
MMS-Proxy
MMS-Port
MCC
MNC
Authentication Type
Max. Message Size

The following settings are not specified by the carrier (device preset values in brackets) or even non-existent in the device menu (x):

Mobile Data:

Proxy
Port

MMS:

APN Type ("default, supl, mms, xcap, email")
APN Protocol ("IPv4")
APN Roaming Protocol ("IPv4")
Bearer ("none")
Mobile Virtual Network Operator Type ("none")
Max. Message Size (x)

...not sure where this belongs:

Server

What are the correct settings? What about the following:

Authentication Type: "empty" (carrier) - vs. - "PAP" or "CHAP" (isn't the latter more secure?)
Bearer: "unspecified" (carrier) - vs. - e.g. "LTE" (doesn't this affect speed?)
APN Protocol, APN Roaming Protocol: ...shouldn't this be set to "IPv6"?
Mobile Virtual Network Operator Type: "none/SPN/IMSI/GID" ...what is this?

Those configuration messages usually just set the APN and may be some proxy settings (depends on the carrier). Carries often have a manual what APN values to set by hand. Search on your carriers home-page for it.

Thanks, this is a good start. I've updated the question!

If you have applied the settings and nothing has changed then I doubt that this is a configuration issue. May be the speed is limited for your contract (very typical for a mobile contract in Germany) or your device is too old or not perfectly compatible with the frequencies used by your carrier. In any way as you neither tell use your exact device model nor the exact carrier and data plan I don't see how we could help you further.

Your settings are carrier specific, any settings not specified by the carrier should be blank or default... That said, this is NOT an Android specific related question in any way, but is generic. Voting to close.

Device model, carrier, and data plan have been added to the question. What about the Authentication Type: I tried empty/PAP/CHAP and all settings seem to work (full connection). Also, is it technically possible that any of the last three settings (Bearer, APN Protocol/APN Roaming Protocol, Mobile Virtual Network Operator Type) have any influence on the bandwidth? Btw, this IS an Android-related question (please read carefully).


text:
Unlocked boot loader ADB issue
So I’m trying to downgrade my nexus 6P from Oreo 8.1 to 7.xx. I’ve unlocked the boot loader and can communicate with the device through Google’s adb fast boot command line which works fine (up to a point) I get this far and it fails every time. Here’s the files I’m trying to flash. Is there something I’m missing? I’ve installed google usb drivers too as I thought that was the issue
https://i.stack.imgur.com/QHqmk.jpg
I’d like to pay whoever can resolves the issue, can send crypto

You should open the flash-all.bat file in an editor and check which fastboot command it tries to execute after displaying checking version baseband.


text:
How do I use my SmartPhone to USB host my old Tablet?
My new moto g7 does not Wi-Fi the correct frequency for my old dragon touch X10.  Android 9 on phone and 5.1.1 on the tablet.  Want to Host from cellular through USB to Client tablet. Any ideas on how to get the internet connection through? Tried PDAnet+ but both devices seem to HOST and I need tablet as client...

Your phone is connected to internet, right? So if your phone supports USB tethering it'll appear as a USB Ethernet adapter on your tablet which must be supported on your tablet, but is highly unlikely. PDANet requires a client-side software (on PC) which is not available for phones (in USB OTG mode) AFAIK.

What is the exact problem with the Wifi frequencies? Does your new phone use a unsupported/disallowed channel in 2.4GHz (which one?) or does it only provide a 5GHz hotspot?


text:
Google two-step verification doesn't want to work. Pops up, I approve and nothing happens
Phone is a Samsung Note 9  SM-960F model. The phone is running Android 10. And I never experienced this problem on any other phone, model or Android version before.
Basically I am logged into my Google account. Every Google service works great. Except two-step verification.

I get the "notification" in Chrome for example when I sign in on a new PC. All great.
The phone makes a notification sound, the two step verification pops up.
I tap "Yes", I get a toast notification "Approved".... and nothing happens.

What could cause this and how could I fix this?

I've encountered this issue before and in the end it turned out to just be a server-side outage / traffic.  Either wait it out after submitting or try again in a bit if it times out, but don't spam requests as it'd likely contribute to the delays.  Feel free to confirm it's not an network/carrier/ISP connectivity issue on your end first (e.g., switch to mobile data or vice versa), but when it last occured I was quite peeved there was no mention anywhere on Google's end in support resources regarding ongoing outages.

Fair enough, thanks for the answer. Thought it's something on my end...

I just had it now: Clicking yes has absolutely 0 impact on the button, as if the screen is frozen (no button vfx).
For me, the solution was to either reboot the phone and/or disable VPN: One of these two did the trick immediately after the reboot was done!