Check this app: activityLifecircle2.aia (33.7 KB)
(with Companion or APK):
Open the app, press the device power button to set the device in idle (sleep) mode (black screen), wait ... and bring the app to the foreground.
Question: Is the counter (sec) running?
The app uses this (new) extension: Extension - Activity Lifecycle of an app (onPause → onStop → onResume)