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.
OT - Fabfilter Pro-R (for computer) Giveaway from ProSound Effects
This is just a way of ProSound Effects building up their mailing list, and they're only giving one away on November 1st.
But still... any penny in the wishing well for a copy of this magnificent reverb.. It's $199 for the computer. 
https://www.prosoundeffects.com/blog/giveaways/fabfilter-pro-r-giveaway/?lucky=20176
Comments
When I remember how expensive FabFilters are on the Mac, I appreciate Auria Pro even more...