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.

It's published by Gameblyr, who previously released the Silver Award-winning Pathogen and the Bronze Award-winning Third Eye Crime.

Grab it on the App Store for more than half off if you're up to the challenge.