Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.
Download on the App StoreAudiobus is the app that makes the rest of your setup better.
Audiobus 2 Bug: Saving presets with "/" in the name
When saving presets, if you put a slash, "/", in the name, the preset will save but not be visible in the presets list. If you save it again with the same name, an incremental number will be added to the preset name, but it still won't show up in the list. I'm guessing this is because the / is interpreted by the file system as a sub-folder?