title: How can my IOS app know when the multitask bar is shown?
body: <p>For the most part my app handles this action with no issues. However, at one point I have a sound looping playback and if the home button is double tapped to open the multitask bar, the sound just continues playing until the multitask bar is closed and it ends its sequence.</p>
  
  <p>I would expect there to be a UIApplicationDelegate method that is called for this action, but I can't find any documentation of it.</p>