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.
Track - Polyphase Session 1
@waynerowand showcased Polyphase with Model 15 and I remembered loving the Beta so I bought it and made a track too:
I sent each of the 4 Midi outs of Polyphase to a different App in AUM.
The Choir sounds are played by me using a StreamByter "Power Chords" script but Polyphase stays within a programmed key (A minor with a shift down to D minor in the middle) so everything fits together well.
NOTE: Send the AUM MIDI Clock to Polyphase and in Polyphase set the MIDI clock to Polyphase.
Then you can start/stop Polyphase from AUM's transport controls. Open Polyphase in AUM as an IAA instance. It make flipping between Apps and Polyphase easier. You can also run Polyphase independently and send it's MIDI into AUM and set Apps to the configured MIDI Channels.