For years, there was only one choice for gaming on the move but this Christmas, two portable systems - Nintendo and Nokia - are going head-to-head

GAME BOY ADVANCE SP, Price: deals vary - expect to pay about £89 for the unit alone.

PROS: Unrivalled selection of games, lots of add-ons, fantastic battery life for a unit with a colour screen.

CONS: It may only be a couple of years old but the hardware is starting to look old, unlikely to hang around as long as the Game Boy before a replacement arrives, costs ten quid more than a GameCube.

NINTENDO started the hand-held phenomenon with its Game & Watch units so there isn't very much it doesn't know about gaming on the go. The original Game Boy remains the world's favourite console. There can't be many homes with kids that don't have a battered example kicking around in the bottom of the toy cupboard.

Game Boy Advance is a far more proficient machine, capable of running sophisticated software aimed at children and adults. Comparing old with new is as unfair to the original as putting the PSOne side-by-side with the PS2.

It's a sign of how successful the platform has been that Nintendo now asks ten quid more for its hand-held than the far more sophisticated (and expensive to manufacture) GameCube.

Nintendo resisted the move to a colour screen for years, saying the hit a hand-held suffered in terms of battery life wasn't worth it. The death of rival colour screen consoles such as the Game Gear and the Lynx seemed to bear that out. The colour screen on the Game Boy Advance SP is incredibly parsimonious, with its power meaning the little unit can still run for several days before it needs juicing up.

Nintendo having the hand-held market to itself for sometime now has led to a steady flow of decent games. All the big franchises can be obtained for a GBA. There are also scores of accessories such as magnifiers, headphones, docking stations etc.

On the downside, even if the Nokia N-Gage fails to dent the GBA market (and the signs are there for all to see) there is a much greater threat to Nintendo's traditional cash cow. Sony is working on a hand-held that promises to pack a real punch (somewhere between PSOne and PS2). If it can make good on the potential of such a unit then the GBA may well be dead in the water.

NOKIA N-GAGE, Cost: price varies according to your mobile phone service contract - lots of shopping around needed.

PROS: Games look better than the GBA, on-line options.

CONS: Is it a games machine or a fancy phone? With so few sold, how long will third party developers stick around?

THE Nokia N-Gage claims to be the future of games machines - a console you carry in your pocket that doubles up as a phone and a rudimentary PDA. Nokia reckons it is the perfect lifestyle accessory, as at home in a business meeting as it is on the back of a bus playing Tomb Raider. Which probably accounts for the misunderstanding that seems to surround N-Gage at the moment.

When I did a straw poll in the office, only two people knew what it was. Of those two, one thought it was a mobile phone, the other a hand-held games console.

They were both right. Nokia has bundled a very powerful games machine into a run-of-the-mill phone handset. Unfortunately, as a hand-held, the phone facilities make it damn expensive (although a contract reduces the stiff price considerably, albeit at the expensive of regular monthly payments) and, as a phone, the games aren't as cool as a web cam or full-blown PDA facilities.

The software has been fairly impressive so far. Don't believe me? Then load up the Tomb Raider game and watch your pals turn green with envy. The on-line aspect of N-Gage also remains an intriguing prospect.

Other aspects of the unit betray a fundamental lack of understanding of the gaming community. Why, for example, does the handset have to be partially dismantled to do something so simple as changing a game cartridge? Nokia is rumoured to be redesigning N-Gage to overcome this but why wasn't it picked up before production and what will that do to the residuals of mark one versions?

I can't really see too many N-Gages elbowing the GBA out of the way come this Christmas. It's a brave step but the wise user may be best served to see how this market pans out.

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