Where's the manual? I don't get it (the UI).
To start, hit the button that says Start. Then click on the matrix to add or remove notes. To add a fill, click the Fill button. To change the tempo, rotate the Tempo knob. To clear the notes and start over, click on the Clear button. I can understand that it might not make sense to someone who hasn't seen or used a TR-808, but it's been a staple of multiple forms of music since it was introduced 40 years ago.
Imagine the ramifications for someone who wanted to teach a course on programming synthesizers if having a hardware synth was no longer a barrier to entry. (You can say a computer is a barrier to entry, but let's face it, computers and iPads are used for lots of things, not just learning how to program synthesizers. Odds are there's already one in the average household, and Chromebooks are getting cheaper all the time.)
This kind of thing could even be embedded in an online course, sort of like how you embed videos, except this would be interactive.