Each version of Android has Easter eggs that you can access by taping your device’s Android version several times. If you have Android KitKat installed on your device, taping the Android version will launch a game that fills your screen with colorful tiles. Each tile represents previous versions of Android such as Donut, Eclair, Froyo, Gingerbread, etc.
To unlock the hidden game (Easter egg) on Android KitKat powered devices, go to Settings and tap “Android version” several times. A big “K” will appear on the screen. Press down on this to launch a KitKat chocolate-bar style logo, and then press down on this to launch the game.
Older versions of Android also have Easter eggs that you can access by following the same way. For example, on Ice Cream sandwich devices, you will get an animation of flying Android logos wearing ice cream sandwiches.