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.
OUTTA BASS: Overlooked Gem?
I dare say yes.
This is some semi modular analog really powerful synth app and I am shocked more people don't talk about it.
I think it got released at a bad time when something else big dropped.
I think this app is well worth it.
No, I don't know if AU is in the cards or not.
Link, I don't know. Doesn't matter to me for a synth anyway.