I’ve had a chance to try out Mathemachicken, by @azamsharp. This is an app aimed at kids.
The UI is slow to respond, while at first I thought it was some BED PROGRAMMING, i realized it might be intentional: kids are slower to respond, and if really a tutor, the app should be resistant to proning by the kids. The chicken and the cow are your teachers, and this app is all about teaching kids to add and subtract.
The main menu is pretty much explanatory, you can add and subtract.
Hitting it right is met with HUGE applause.
Doing it wrong, you hear the usual fail sound.
This app doesn’t conform at all to regular UI.
I looked for a way to get back to the main menu, but there was none. Instead of just quitting the app, I touched a Home icon. A literal drawing of a house. It took me to the main menu.
All in all, it’s not a fantastic app by any means, but if you have kids, kids don’t care about that they just want something cute and resistant to damage. Mathemachicken doesn’t feature any in-app purchases or the like, it’s just a visual representation of adding and subtracting, and if you’re looking for that, this might be it.