Memorize a sequence of tiles which is shown to you and reproduce it by touching the tiles in the right order. To adjust the game’s difficulty, you can vary the speed the sequence is shown to you and its length.
Sidenote: At the point of posting this program has been marked as beeing freely available without costs. As this program is hosted with the AppStore the status might change. Authors like to publish their programs for free for promotion purpose and then make it commercial. Also it could happen that the author decides to take the program down.