It might work to generally limit CPU and network resources usable by processes not actively foregrounded in the GUI. Linux cgroups is good for this sort of thing.
A bit like some browsers do to timers in non-foreground tabs.
It would simplify development quite a bit if this solution ends up being sufficient for battery life. No need to think about onCreate, onResume, onPause, onStop, onRestart , etc. like on Android.
But RAM might also be a problem if the phone keeps everything in background & isn't allowed to kill any app when it needs to
But RAM might also be a problem if the phone keeps everything in background & isn't allowed to kill any app when it needs to