It may have appeared stylistically handicapped next to Sony’s PSP, but Nintendo’s over grown Game & Watch, the DS, spawned four different incarnations and sold 144.6 million units, leaving its sleek and glossy opposition choking on dust and failed UMD debris.

Sony must be getting déjà vu: just as it announces the sleek and glossy Next Generation Portable, Nintendo chucks us this green-hued reboot of the DS.

Of course, we already know from the anticipation-building teasers and previews what the killer app is here: a 3D screen that needs no glasses. Ironically, that’s against a market backdrop that’s seeing Sony throw 3D at everything it produces… apart from the NGP. Look, we don’t make the rules.

The 3DS uses autostereoscopy to assign different parts of its graphical output to different sections of the screen and create a 3D effect. It’s a depth-of-field trick, and there’s no denying that it’s very impressive. Landscapes withdraw à la Avatar rather than jumping out at you like Captain Eo. This is put to best use on the pre-installed augmented-reality games, which incorporate your surroundings into the action via the exterior cameras. As you shoot evil encroaching commuters as they emerge magically from the Tube doors, you realise the device’s potential.

However, the 3D effect, which can be adjusted with the screen-side depth slider, is also disorientating and prolonged use can make your eyes feel tired and your brain feel mildly scrambled. Something like the upcoming Metal Gear Solid, which demands your close attention for hours on end, could make us fear for our retinas. There is also a nagging feeling with some games that, much like their cinema counterparts, 3D has been tacked on to raise the SRP rather than enhance the playing experience.

However, the 3D effect is not obligatory. Turn the 3D effect slider down and the graphics still look good in 2D, the customised PICA200 chip powering animations that look smoother than the Wii. Despite the claimed low power consumption of the chip, the full-3D battery life of three to five hours sounds pretty pathetic. Either we’ll all get used to carrying chargers around with us on journeys, or there’s going to be a lot of disappointed gamers running out of charge midway through crucial boss battles.

While the unit may look and feel at first like an old DS with a lick of paint – it’s backwards compatible and the OS offers little you won’t have seen before from Nintendo – it’s now packing both a gyroscope and an accelerometer for effective motion-sensing controls, and an iPhone-style Home button to take you straight back to the menu. Best of all, there’s now a 360-degree analogue pad, which, reclining as it does in its own inset controller bath, is a joy to use compared to the PSP’s bevelled thumbkiller.

The front-facing 640x480 camera can take 2D shots of your chiselled features, while the pair of identical cameras on the outside shoot fairly impressive, if faintly useless low-res 3D pics. Its main use will hopefully be in facilitating more AR games.

The built-in Wi-Fi doesn’t just offer access to an internet browser and eventually eShop game downloads but also other people’s content – although the much-vaunted Street Pass idea, allowing the exchange of data between strangers, is of course heavily hindered by copyright laws.

Elsewhere, there’s a basic AAC/MP3 player, while a built-in pedometer records how many steps you take whenever you are “with 3DS”, and rewards you with in-game extras. It’s an enjoyably quirky addition that’s typical Nintendo – much like the 3DS in general, in fact.

With the NGP not out till “holiday 2011”, the 3DS has a good nine-month run at the next-next-next-gen handheld market. Its only real competitors are the old DS – arguably, the 3DS is too similar to its predecessor in terms of look and feel and too dissimilar in terms of pricing – and smartphones. Do you need a dedicated handheld console with full-price games when your mobile phone can rock PS2-quality games for a few quid, downloaded in minutes? That’s the thorny issue of the day. The 3DS is missing a trick by not having its eShop operational at launch, as old-school, dedicated, portable consoles could turn out to be a thing of the past. Certainly one for Sony to contemplate over the next nine months or so.

As with cinema – and Nintendo is inking deals with film companies to provide 3D movie content too – 3D will be novelty enough to guarantee success, but it’s a novelty that will wear off if not utilised correctly. However, you’d be a fool to bet against Nintendo doing just that, and the 3DS, with its wealth of control options and much improved graphics, is by no means a one-trick pony.

Nintendo 3DS release date: March 25th. Link Nintendo

Nintendo 3DS price: £199-£229 depending on retailer