Mencalc

Practice mental calculation, also called mental arithmetics. After each exercise an interactive graph shows you what went wrong and which calculation took the most time to perform.

The following exercises are available:

- Addition
- Substraction
- Multiplication
- Division
- Modulo
- Mixed

The app currently only supports tablet devices running Android 3 Honeycomb, but a free update will be made available which includes Android 2 support. Let me know if there are other features you would like to see added.

Check out Hexact as well, the hexadecimal brother of this application.