iOS: How do I detect if music is playing in any background music app?

Question

I currently have my game correctly handling disabling its own BGM when music is playing in the built-in iPod app, but it does not detect when an app such as Pandora is playing music.

Currently, in my applicationDidBecomeActive method, I check [[MPMusicPlayerController iPodMusicPlayer] playbackState] to determine whether music is playing. What is the equivalent of this to check if an app like Pandora is playing audio in the background?

Answer 1

Check out this question

Seems you can see if another audio is playing by checking the property kAudioSessionProperty_OtherAudioIsPlaying like this:

UInt32 propertySize, audioIsAlreadyPlaying=0;
propertySize = sizeof(UInt32);
AudioSessionGetProperty(kAudioSessionProperty_OtherAudioIsPlaying, &propertySize, &audioIsAlreadyPlaying);

A complement to this could be to ask the user if he/she wants to have the game music or the already playing sound/music.

Answer 2

AudioSessionGetProperty (as mentioned in jake_hetfield's answer) is deprecated as of iOS 7.

Instead, try this one-liner that uses isOtherAudioPlaying:

BOOL isOtherAudioPlaying = [[AVAudioSession sharedInstance] isOtherAudioPlaying];

Works on iOS 6+.