Your screen looks too clean. Load up Smudges and hand it off to your favorite 2- to 82-year-old, and let them go nuts tapping the screen.
Smudges is a great game for kids of any age. Shapes of all sorts and colors pop on the screen with every tap, accompanied by playful arcade-style sounds. Shapes can then be dragged all over the screen. Smudges recognizes multiple simultaneous taps for fun arrangements and multiple players on the same device.