Cling!

As the title suggests, Cling! is a very tactile experience. Protagonist Edgar is a purple blob who is able to stick himself to the various pegs which appear in each level using his freakish appendages, and he exploits this talent to move through each stage and reach the exit.

Cling!'s control system is a real triumph, offering both simplicity and a surprising degree of depth. Moving Edgar around is a case of tapping the direction you'd like him to head towards - as long as there are some pegs for him to cling to, he'll dutifully oblige.

However, Edgar is subject to the usual laws of physics, and as he moves he builds up momentum - momentum which will carry him off the edge of the screen and into the abyss if the row of pegs ends abruptly. You also need to be aware of gravity's pull, which can sometimes cause our hero to drop off the bottom of the level.

These elements aren't the only threats you'll face during the course of Edgar's adventure. Spike pegs offer a clinging point but will kill Edgar if his body makes close contact with them.

Deadly blocks have a similarly fatal effect. These hostile forces are introduced gradually, but it doesn't take long for Cling! to transform into a fiendishly challenging exercise in reactions and coordination. Timing your runs and judging where Edgar's momentum will take him are tricky tasks.

There are additional characters to unlock, as well as a dazzling range of hats (don't ask), but it's Cling!'s stern difficulty that's likely to keep you glued to your iPhone for a considerable amount of time.

This is not an easy game by any means, but it rarely feels like it's being unfair - your objective is clear and it's fairly obvious what tactics you need to use. The challenge lies in being quick and clever enough to reach the end of each stage.

It might prove too hard for some players, but Cling! comes recommended nonetheless, offering just the right balance between puzzling and reflex-based action.