The success of T-Mobile's Sidekick is perhaps mostly to do with the way the screen opens.

Flick it with your thumb and the spring-loaded mechanism wheels the screen round to reveal a full Qwerty keyboard underneath. It’s neat and, more importantly, cool. It’s one of the ways the T-Mobile Sidekick 3 identifies itself as a phone that teenagers and young adults will want.

The technology inside is aimed at pleasing kids and bewildering dads, too. So there’s instant messaging and texting readily accessible, and, when activated, the Sidekick 3, creates a unique email address for you.

Although not over-complicated, using the Sidekick 3 will need to be honed. The menu and navigation buttons are not clearly marked and the power button is well hidden, so knowing how it all works makes you part of a private club.

Unlike earlier Sidekicks, this one has a media player built in, with music stored on micro SD cards (though only 64MB is included). There’s also a camera – at 1.3 megapixels it won’t make you David Bailey, but it’s good for fun, message-friendly snaps. The Sidekick 3 works as a decent handheld computer too, with contacts, and calendar functions easily reached.

The navigation method, using a rolling ball similar to that on the Blackberry Pearl, is simple enough, too, complemented by a direction button at the other end.

There are other neat touches; the keypad is backlit, but only when it needs to be. Use it in bright light and keys are lit clearly, but nip into an achingly hip (dimly lit) bar and when the Sidekick 3 senses it’s dark, a gentle glow will light up behind the keys. And the large colour screen is ideal both for surfing the internet and playing games – it comes with a version of Asteroid called Rock & Rocket.

Web browsing is slowed by the fact that it’s not a 3G handset, which also rules out video calling (which might have been a teen-friendly addition), but none the less, it’s a pretty attractive proposition.

Also consider:
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Palm Treo 750v
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Nokia E61
The Nokia E61's Qwerty keypad and email support make it a clear rival for RIM's Blackberry

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