For example, if I want to know when Youtube is open, is there any broadcast associated with it? I know, of course, I can poll the logcat message to check activity. But can I do this through the broadcast, as it will be much less hungry.
This link seems to indicate that this is not possible: < How to track application usage in Android? How to determine when an activity is running?
Is there any broadcast in adroid when some application is open?
No, for obvious reasons, privacy.