Icycle: On Thin Ice is a thing to behold. As its levels deform and reshape themselves, cracking into shards and collapsing all around your ever-panicking avatar, you can't help but be impressed. And these are far from just visual changes.

Each deformation is a new pathway, a split-second test of reactions, or a fresh set of obstacles for you to pedal over. It makes for a continually enthralling experience, and one where you're never entirely sure, at least for the first play-through, which direction you're supposed to be going.

I cycle, you cycle

The game is essentially a platformer. You're in control of Dennis, a man who finds himself lost in a series of different frozen worlds with nothing more than a tiny bicycle to help him through the ever-changing landscape.

Two direction buttons on the bottom left of the screen control your movement, and a button on the bottom-right lets you perform little jumps. Holding it for longer makes you leap higher, and pushing it again once you're airborne pops out an umbrella that lets you float for a while.

The platforming is reasonably smooth, and mixes measured hops with desperate chases. Some levels test your reactions, dropping chunks of scenery on you and forcing you to change direction rapidly to stay alive.

The variety in play styles is reflected in the levels. While everything starts in a frozen waste you'll soon find yourself in a shattered city, a bizarre sweet-filled dream world, and in an undersea adventure that culminates in a fishy smooch.

There are chunks of ice to collect in each level, and you can spend them on a variety of different boosts and upgrades to aid you through your travels.

Each of the sections has a set of challenges too, giving you plenty of reason to jump back into them.

Cold hard facts

Icycle: On Thin Ice is an ingenious mix of ideas, but it's not without its flaws. Sometimes things can be a little on the cruel side, and being crushed by a chunk of falling ice you didn't have any chance of avoiding is especially annoying when it takes away your last life.

The niggles are minimal, though, and don't detract too badly from what is a lovely, engaging experience. Icycle: On Thin Ice is a game full of wit and charm that shows just how great iOS platformers can be.