I have looked through the developer library and found much useful info but still no answer to my question.
The question: Is it possible to have my app run primarily in the background, monitoring the audio route of the phone in general, and reacting to any change in the route with whichever code I choose? I understand that I must keep within the guidelines of apps running in the background and providing a useful service.
Also note that this app would not have any audio session of its own, it does not need to play or record audio, only monitor the route change (e.g. headset being unplugged).
Hope someone here knows more than I do and can give me a tip!