An experiment in touch based controls of pitch and volume for multiple tones resulted in an app that's fun to interact with, and produces a wide range of different sounds and textures.
Drag some dots into the work area and carefully position for controllable out of phasing, or shake the device to randomize the whole mess.
Use touch to position up to 40 tones in the work space
Slider controls for motion setup
Pause so you can grab the fast moving ones
Save/load your compositions (can they be called that?)
Auto save/load of active composition when exiting/starting app
Shake device to randomize all active tones
Individual tone randomization option