Im a bit confused on background limitations of apps, and I could use an explanation. So, starting from android 8 we have limitations on services and sending broadcasts. As for now, we can only make service run in background if it has the foreground notification, otherwise it will be killed. The app is considered to be in background if none of it's activities are visible, and my questions are: 1. For how long can the app-process itself live without foreground service? For instance, if I go to home screen, thereby putting app in background my app can still play sounds for hours, but I expected it will be killed by system in a couple of minutes. 2. Is foreground service somehow related to application lifecycle? For instance,maybe if I start the foreground service then my app won't get killed or less likely to be killed by the system.
I'm asking all this because my app is using c++ libs to make VOIP calls and do other stuff in background and I'm wondering what would happen if I just open the home screen and leave my app working, so far I've never seen the system kill the app while the call is active.