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.
External Modulation Sources - ZOA
I have followed step by step what he shows here but can't get the velocity to modulate...
In the ZOA menu, connecting to Rozeta LFO - disabling all except top on Rozeta as per tute.. Rozeta is Channel 1 and the Cc is 13. Going to the Midi preferences of Zoa, playhead 1 and changing the velocity to channel 1 - cc 13 - hit play and nothing..