First of all, super duper shout-out to Luke Phillips for his theremin app.
I'd checked this out some time ago, but didn't start really putting it through its paces until a few weeks ago, getting a good sense of what soundscapes it can put together just using its own looping/overdubbing features. I decided to make a small project out of it due to it being criminally underrepresented on YouTube apart from Phillip's own demonstrations. Saying that, though, I didn't have a good setup for filming the actual composing/performing that I was happy with. I figured it would be more in line with the spirit of musique concrete to let the sounds speak for themselves.
This is a roughly 50% improvised composition using a theremin app on an Android device pumped through a bass effects pedal's ring modulator setting. It was all recorded in one go with no post-processing on a Zoom H2N. When I say 50% improvised I mean that I had criteria for what notes to use, what waveforms to use (only square and sine wave), what pedal settings to stick to, and what an acceptable overall length would be to convey (if only in an abstract sense) a suggestion of a narrative.