I found myself in a strange underwater world, where light things float up and heavy things sink down, leading to some very interesting puzzles.

After that, I found myself back on dry land, but now, as well as bombs, I have balloons I can use to make things float.

My general way of playing this now is to do a level, get scared by the next one and quit the game. Then, a few minutes later I’ll start it up again and be put back exactly where I left off. No menus, nothing – straight into the game. I’ll realise the level wasn’t as hard as it looked, though it’ll probably take a far bit of experimentation, then I’ll see the next level, quit out and the cycle begins anew.

It’s fabulous.

(People who set iPhone game prices take note – a launch sale does wonders to turn “new release interest” into “must buy before price goes up.”)

It’s basically a physics puzzle game, where you place bombs and adjust their timing to blow little round chaps into the exit vortex.

It’s gorgeous, for starters. No, look.

Gorgeous. Not that that screen shot shows it off at its best.

It’s very well designed, with helpful hints that don’t turn into a dull tutorial. It starts easy, then gets harder. I’ve only down the first world and part of the second, so it’s all been pretty easy so far, but there’s been a noticeable, though shallow, upwards curve. Also, you can instantly reset the level when you fail with all your bombs in place, so you can instantly tweak, not recreate.

It’s brilliant.