It'd be great to have other sensors available for performance beyond the gyroscope, though I don't really know if all of these are truly accessible for non-Apple apps.
You could try to route the MIDI from https://www.musikraken.com/ into Drambo. Just in case you have other mobile devices: MusiKraken runs on Android as well, so you could even use an Android tablet or phone as sensor.
@catherder thanks! I wasn't aware of this
Or you could just use noise/random modules.
Im not dismissing this quest, in fact it’s one I chased, but in the end one random is not better than another, in regards to musical applications (as opposed to crypto, fe)
And besides the gyro, you can use the mic and pitch/env follower. That has me covered