Size may not be everything, but a phone that slides so easily into your pocket that it almost disappears makes a virtue of its smallness. Slider phones usefully keep the keypad hidden away behind the screen so you can’t make calls accidentally (dialling the first name in the address book by the pressure of buttock on phone keys is more common that you’d think).

They’re also more compact than clamshell-style phones, and the D900 is part of Samsung’s Ultra range of especially slim handsets. Its admirable slimness, however, guarantees that this is not a 3G phone.

Samsung has regularly made good sliding mechanisms, with the right amount of spring to open and close the phone with minimum effort. Here, a raised ridge just below the screen makes opening the phone easier than ever, and reduces thumb prints on the screen.

Though the D900 is remarkably thin, it still works well. Samsung’s earlier slim slider, the D800, had keys which didn’t move much - you barely knew whether you’d pressed them or not.
This is much more satisfying, and the only drawback to the keypad is that a raised lip at the bottom of the phone is so close to the 0, * and [hash] keys that they are less easy to get to than the others.

Samsung's quirkiness is to the fore, with gently animated wallpaper depicting the Houses of Parliament. This changes as the time does, darkening at night, lighting the sky with fireworks when you have a message and changing to picture of the countryside when you're out of network coverage.

Travel abroad, and the image changes automatically, to St Basil's in Moscow, the Sagrada Familia in Barcelona and so on. It's slightly pointless, but quite charming.

There's 80MB of memory on the phone, with a micro SD card slot available to add more capacity for music or pictures, and as the phone supports A2DP (that is, stereo) Bluetooth, you can play tracks through wireless Bluetooth headphones.

The camera is an impressive 3megapixel model, and it’s mounted behind the slider, so it's protected when the handset is closed. Of course, you can shoot video, too, and output it all to a TV if you want.

Samsung's operating system is straightforward and easy, though texting can be irritating. It's much improved (automatic capital letter at the start of a sentence, for instance), but if you want a capital mid-sentence, you have to press the capitalisation key twice - once just changes the input to numbers. On the whole, though, it's still an appealing set-up.

Samsung's D900 is proof that a fashion phone needn't be function-light, and that a decent cameraphone needn't be bulky. Impressive.

Also consider
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Rating: 4
Price: From free depending on contract; £199 (pay-as-you-go)

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