I've added a new OS X project on GitHub that shows how a simple oscillator created with AudioKit can be controlled with a physical interface. It's written in Swift, and uses the ORSSerialPort library to interface with an Arduino Uno. I've published a demo video of the project on Vimeo.
A detailed description of how the app works can be found in the project's README file.
I hope you find it useful! If you have any questions, or use it as part of your project, please let me know!
Nick
nick (at) audiokit (dot) io