2048 free - sliding number puzzle game

feature:
- Support REVERT. Never worry about making a wrong step.
- Support LEADERBOARD. Compete with players all over the world.
- Support 4x4 & 5x5.
- Support GameCenter

2048 is a single-player sliding block puzzle game. It is played on a gray 4×4 grid, with numbered tiles that slide smoothly when a player moves them using the four arrow keys. Every turn, a new tile will randomly appear in an empty spot on the board with a value of either 2 or 4.
The game is won when a tile with a value of 2048 appears on the board