If the iOS implementation of Core MIDI eventually supports playback, then I can eliminate "Sounds - m4a" (mostly .m4a files) and replace those sounds with the standard .mid sounds in the "Sounds - midi" folder, which the Mac version is using already.

If I'm really lucky, the same Core MIDI code will run on both iOS and macOS.

Note:  I experimented with MIDI playback on iOS. At first glance it looks pretty simple, something like

		NewMusicPlayer(&theMusicPlayer);
		NewMusicSequence(&theMusicSequence);
		MusicSequenceFileLoad(	theMusicSequence,
								(CFURLRef)theFileURL,
								kMusicSequenceFile_MIDIType,
								kMusicSequenceLoadSMF_ChannelsToTracks);
		MusicPlayerSetSequence(theMusicPlayer, theMusicSequence);
		MusicPlayerStart(theMusicPlayer);
	//DisposeMusicSequence(theMusicSequence);
	//DisposeMusicPlayer(theMusicPlayer);

but then one realizes that iOS provides no default instruments.  One apparently needs to provide one's own SoundFont or DLS file, and also set up an AUGraph.  Ugh.
Update:  As of iOS 8, it seems one can use an AVMIDIPlayer to simplify this procedure.  See

	http://www.rockhoppertech.com/blog/swift-and-avmidiplayer/

Alas it seems one still needs to provide a SoundFont or DLS file.
