The self-proclaimed "most challenging puzzle game on iOS," Zengrams, is on sale right now for 69p / 99c.
Does it live up to its claim? If you think 66% off £1.99 / $2.99 is a good bargain, you can find out now on the App Store.
Zengrams is an abstract puzzle game about rearranging shapes into various designs with a limited number of moves.
Grab it on the App Store for more than half off if you're up to the challenge.