http://itunes.apple.com/us/app/menace-synth/id1387317830?ls=...
Here's a teaser video:
https://www.instagram.com/p/BlgMTAGlv7c
I created Polychord back in 2010 – one of the first iPad music apps, and still used today by thousands of musicians. With Menace, I wanted to do something more experimental, a little out-of-bounds.
Menace was built on AudioKit [1]. Having built apps on Core Audio for a long time now, I can't recommend AudioKit enough.
The other thing I'll mention is that this was an experiment in embracing a principle of getting something in front of real people as soon as possible, and iterating continuously based on their feedback. The app was never more than a day away from 'finished'. I was inspired by Ron Jeffries essay, "Developers should Abandon Agile" [2] – it was a guiding light for getting this project together quickly (over roughly a couple of months of spare nights and weekends).
Happy to answer questions!