For the most part apps that are in the background (i.e. not the app that has focus) are in an idle state. They may be doing something like updating your weather or syncing your messages, but for the most part they're just waiting to be:
- brought to the foreground to do whatever they're supposed to do
- swapped out of memory if the OS needs it
You can use something like SystemPanelLite Task Manager:
https://forums.androidcentral.com/e?...token=3eZO9L50 to get an idea of which apps and services are always running versus which ones are running right now, and you can even end tasks but it's usually unnecessary unless you have a runaway app, and if you have one of those the solution is to uninstall it.
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