Occasionally a game is so popular and so loved that it gets released on every platform under the sun. Few games can beat Peggle on this front. Available on everything from home consoles to mobile phones, Peggle is virtually omnipresent. There is no escape, and now it's on iPhone too.

Somehow, each version manages to sell amazingly well too, even though they all tend to feature the same levels. The key is of course that the gameplay is just so fantastically, well, fantastic.

It's confoundingly simple too. All you have to do is to launch a little ball into an arrangement of pegs, much like a game of Pachinko. Unlike that Japanese favourite, the pegs disappear shortly after your ball has hit them.

In each level, your aim is to get rid of all the orange-coloured pegs using precisely this method, with a limited number of balls at your disposal. However, even though you can direct the initial trajectory of your ball, either by touching on-screen where you want it to go or by using a scroll wheel to the far right of the screen, the realistic physics make it near impossible to judge where the ball will eventually end up.

Well, the ball's always going to end up falling through the bottom of the screen, but you ideally want it to fall into the ball catcher that moves back and forth underneath the pegs. Get it in here and you'll win an extra ball.

You can also win extra balls by scoring a certain amount of points using a single ball, while there are 10 different power-ups to unlock by playing through the 55 levels that'll boost your peg-smashing power. These range from fireballs that smash straight through the pegs to ones that show where your ball will end up several bounces down the line as you're aiming.

Categorising exactly why Peggle is so engaging, when you're generally at the mercy of the game's physics, isn't the easiest thing to do, but the feedback you get whenever you do something well definitely has something to do with it.

There's constant positive reinforcement in the shape of sound and visual signposts, and winning yourself an extra ball is bizarrely incredibly rewarding. Just watching your score bar rise up to the point where another shiny ball drops down is exciting.

With Peggle, Popcap has hit upon a golden formula of gaming. Even though it's right there in front of your eyes, you won't quite be sure why you're enjoying yourself quite so much. And yet you will be enjoying yourself, and that's what counts.