Collection of insights in Samsung behaviour

[HenrikJannsen]

I test with a Samsung A56 mobile and it behaves different as expected. Here is a collection of things I discovered.

• Swipe out app from current tasks does not destroy the app as usually, but Samsung puts it in background. It seems the the first time it gets swiped out it gets destroyed but after that its sent to background.
• After force stop an app the killed app screen shows still up in current tasks (might be also the case at other phones)
• In emulator I see 2 processes (Bisq and Tor) and 1 Service (Foreground service) at Developer Options/Running Services. In Samsung I see only 1 process. But seems thats only a UI issue in Running Services.

With those commands you get the 2 processes at samsung

# With `adb devices` one get the device ID
adb -s <device ID> shell ps | grep network.bisq.mobile.node
adb -s <device ID> shell ps | grep libtorexec.so

I have also seen duplicated activities of Bisq being created when clicking the app icon. But I cannot reproduce that anymore, might have been caused by some bug which got fixed in the meantime...

[rodvar]

Thanks for documenting the insights in a discussion Henrik, we might add conclusions on this into the project docs.

My 2 sats on this:

• Samsung's "Smart Stay" task manager, which often caches processes to improve perceived performance.
• The app process may be kept alive until memory pressure forces it to die.
• For this reason as devs we can't rely on onTaskRemoved() Android API for example
• don't rely on Samsung UI, they hide and manager things different supposedly based on focus group UX research, the adb commands you listed are the correct way to check existent processes
• double activities launches can happen in samsung but we already have the setup to avoid that in our Manifest (singleTop process and exported )

Just a quick headsup, re After force stop an app the killed app screen shows still up in current tasks you need to know that in Samsung the task thumbnail can stay visible even though the process is fully dead..... I know 😆 - so yeah is confusing but doesn't mean the app is alive, a tap would launch a fresh new process

Always bear in mind that Samsung’s aggressive process management can:

• Kill background services more eagerly unless they are ForegroundServices.
• Delay delivery of lifecycle callbacks (like onDestroy()) when putting tasks in background.
• Sometimes “pre-warm” the process after a swipe-in, which may explain some of the different startup timings you might see.