Mostly good content
When the app goes into background, the player forgets the last play position, that is rather annoying. Video content is mostly good, and it‘s structured in may small sections so you can easily review certain parts if required. However, the author obviously did not understand at all how track mode works, you can have a lot more than 36 bars (I think 255), and each bar can also be transposed individually. I get that nobody uses tracks mode on a real TB-303, but it‘s a lot more usable on the TB-03 due to the display. A few other omissions, like transposing patterns on the fly in pattern play mode, and the explanation of the recording modes could be more to the point.