Pawn'd was one of the nominees for Game of the Week in these TouchArcade forums this past February. A new Free version of Pawn'd has just been released.
Pawn'd combines the strategic thinking and unique moves of chess with fun, gem-shattering, puzzle-game action.
iTunes Link: http://itunes.apple.com/us/app/pawnd-free/id514376756?mt=8
Pawn'd has earned a 5 star rating in iTunes, with dozens of glowing reviews (many from people here!) The free version includes the same games types, with in-app purchase to unlock unlimited play.