A free program for Android, by Miroslav Kisly.

The free app “15 Puzzle” lets you play the classic 15-puzzle game with ease. The difficulty levels range from easy to extremely difficult. 

If you’ve never played the classic 15-puzzle game before, you’ll learn how to play it in a few minutes. It’s easy to learn and fun to play.

To get started, simply tap on a tile to place it in the right spot. You can only move a single tile at a time.

There are no time limits, and no extra prizes or bonuses to play for. If you get stuck, you can simply skip to the next level.