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 Store
Audiobus is the app that makes the rest of your setup better.
Rooms!: Wait for 3.41 if you are on iOS 7
Rooms! 3.4 was released yesterday. I was informed by a user that IAA does not work in 3.4 (you get an error message at app startup). The cause is that the IAA entitlement is missing in the app bundle, for unknown reasons. I compiled the project again (identical code, identical project settings) and submitted version 3.41. This time the entitlement is there. So if you are on iOS 7 and use IAA or don't want to get this annoying error message at every cold start of the app, better skip 3.4 and wait for 3.41.