If you're a fan of old-school space shooters then get set for a high octane blast from the past on your Pocket PC handset.

Krystaloids is a modern reworking of the time-honored format, which delivers all the fun of the original in a superbly-packaged game environment. In terms of the way it looks and sounds, it's more the kind of blaster you'd find in the arcades rather than the sort you'd play at home on your Commodore 64. The sprites are well rendered and smoothly animated and the celestial backgrounds are simply out-of-this-world.

The game itself plays much like asteroids. You need to traverse space in your rocket avoiding meteors and blasting any baddies or debris that hurtles your way. The control system is pretty easy to get used to and you just need to spin your craft in the direction you want to go then hit the accelerator. Along the way you'll get the chance to scoop up power-ups in order to improve your weaponry or defense systems.

In terms of game options, Krystaloids isn't terribly exciting. There's only one difficulty level and no two player mode. That said, you can change the sound and music volume, choose between five languages and toggle the in-game map on and off.

The full version of the game represents an epic challenge and will see you through plenty of bus or train journeys. However, the developer has been particularly mean with this trial version and you only get to play one level with one life and a maximum of three minutes game time.

If you're willing to upgrade to the full version though, Krystaloids represents an accomplished 21st Century reworking of a 20th Century classic.