Is there a way to detect the beginning/ending of voice calls in apps such as Google Hangouts / Skype? (I know this is a shot in the dark, but I was wondering if anyone researched this option).
I'm interested in something like Android's receivers for the android.intent.action.PHONE_STATE and the android.intent.action.NEW_OUTGOING_CALL actions
Skype broadcast:
com.skype.android.CONVERSATION_LIVE_STATE
There u can read:
com.skype.live_identity -> ur friend
com.skype.live_status -> RINGING_FOR_ME or STARTING or NONE
com.skype.account -> your account
来源：https://stackoverflow.com/questions/26795814/detect-call-state-change-in-voip-android-apps