4.3 finally :) I am searching right now how to add air play button to custom view. I have MPMoviePlayer that load movie. I disabled standard controls and added overlay view
In the Documentation Apple also includes a snippet for that:
MPVolumeView *volumeView = [ [MPVolumeView alloc] init] ; [volumeView setShowsVolumeSlider:NO]; [volumeView sizeToFit]; [view addSubview:volumeView];