Gears Gears Everywhere v1.3
Android app on Google Play

Use different types of gears on three different levels to explore the fun of gear mechanics. Free mode allows you to create big systems of gears for your own exploration. Game mode offers 32 levels with a variety of targets and obstacles.

Levels include turning target gears at a certain RPM, grinding coffee, sawing wood and more. Completing levels isn't just about stringing together gears together; gears must be arranged to increase or decrease speed. Score is based on completion time and number of gears used. A lower score is best, so use as few gears as possible in the least amount of time!

There are two types of motors, an engine and a hand crank. Gear alignment happens automatically. Drag and drop a new gear on top of an existing gear and it will line up just right.

Kids Music Maker v1.2
Android app on Google Play

Kids' Music Maker offers 12 keys, which can play notes from a piano or guitar. There are two modes, free play and play-a-long. Free play allows you to play at your own pace and play whatever you please. Play-a-along mode has a dozen common kids songs such as Old MacDonald, Jingle Bells, and Little Teapot.

The beat speed can be made fast or slow and in play-a-long mode, a ball bounces over the keys indicating which note comes next.