Check it out, 100% open source: https://github.com/samuelclay/turntouch-ios. The Mac app, the firmware, and even the CAD and CAM designs are also there. And I documented everything so you can get a peek into how it was built if you want to change the designs for yourself. http://ofbrooklyn.com/2019/01/3/building-turntouch/

Everything I build I want to last beyond myself. So beyond the source code I also write about the why for everything. That it improves sales is a nice bonus.