One of my favorite mobile apps is Mind Wall. It is a simple puzzle game where you need to chip off one square of a wall to fit a tetris like block through the wall. It is mildly challenging, and makes for a good spacial puzzle. It was created for ld48

iOS: https://itunes.apple.com/us/app/mind-wall-universal/id320170750?mt=8

Android:  https://play.google.com/store/apps/details?id=com.rtsoft.rtmindwall&hl=en

https://itunes.apple.com/us/app/mind-wall-universal/id320170750?mt=8

https://play.google.com/store/apps/details?id=com.rtsoft.rtmindwall&hl=en