The 15 puzzle known also as Game of Fifteen is a sliding puzzle consisting of a frame of 4x4 shuffled numbered tiles with one missing. The object of this puzzle is to place the tiles in the correct order from 1 to 15 by drag'n'dropping moves. If you want to solve an image instead of numbers the app offers you some pre-loaded photos, or you can choose one of your own photos.
How to play? See the tutorial or the user manual built in the app.
The images distributed with the app are either mine or provided by my wife Hana Lepková.