HOWL is a simple formant synthesizer for iOS, written in Swift and built using the AudioKit framework. It makes synthesized vowel noises.
Just open HOWL.xcworkspace in Xcode and hit build (as of the time of writing the latest version is Xcode 10.3).
- Reinstate Inter-App Audio
- MIDI input support
- Implement male/female adult/child controls
Just a quick note: HOWL itself is a free app, and I provide the source code free of charge as a learning resource. I ask that you kindly don't put clones of HOWL in the App Store.