XDA member cubewalker has made an awesome app for testing out your math skills on the go using your Android device. The game works by giving you an answer to a problem and then you have to create the problem that would solve to that answer. As you can see in the screenshot, it is done very well. Here is the original post for the app:
Math Scramble is a scrabble-like math game. You need to choose an equation from given number balls to match the target answer. It’s a brain challenge for math lovers.
A longer equation gives higher score and bonus time. Currently we are making update to it. A leader board is under development. If you ever has any idea to improve our game, just email us. We’d love to hear from you!
Notice: support android 1.5 or above. 320×480 resolution or above.
If you want to support our work, just make high rating in market. Thanks!
We hope you enjoy this as much as we do! Go check it out and download it by heading over to the discussion thread._________