How does the 'Play Music' app run without constant notification?
<p>I am writing a metronome app, I have the sound running from a service which I would like to keep running when the user is outside the app (browsing etc) and hasn't made a conscious effort to press the stop button.  </p>

<p>It seems I should be using startForeground() as it's not the kind of thing you want in the background without paying attention to, and I really don't want the service to be killed at any time.  Ideally I wouldn't be showing the notification while the app is in focus though.  I notice that the Google Play Music app works this way, it only shows the notification when outside the app.  Is anyone able to tell me how they have done this, I would find it hard to believe they wouldn't be using startForeground() after reading all the documentation stating you should be using it for this sort of app?</p>

<p>On the other hand, is this really desired behavior?  It seems good to me, but I noticed that pretty much every other app I use with a long running service (HTC's music app, Navigation, few others) shows the notification icon at all times, whether in the app or not.  I am interested in what is considered correct behavior. Any help much appreciated, thanks.   </p>
