IOS Generative Apps: Senode, Riffer

http://discchord.com/appnews/2018/09/28/ajp-senogrid-sonogrid-triggering-senode

http://www.synthanatomy.com/2018/10/audiomoderns-riffer-is-an-intuitive-midi-tool-for-pc-mac-ios-that-generates-random-riffs.html