Swapagon is an interesting puzzle app game. Timo Heister is the author. The object: rearrange the squares on the grid so that the numbered tiles are next to that number of other tiles.
Thus: a 4 needs to be surrounded on all sides by other tiles. Diagonal touching does not count.
We've seen this type of puzzle app game before. This is well done. And hey, it's free!
Is is one of the Best Puzzle Apps of 2013? Probably not. Stay tuned. The awards will be announced at the end of the year.