Sony Ericsson's mobiles are gradually drifting towards Sony's core brands, with a series of successful Walkman music-phones followed by this, the first Cybershot handset.

Labelling a phone as a camera is a brave move, spurred by the K800i's state of the art (for the moment) three-megapixel resolution, autofocus lens and, uniquely, Xenon flash unit.

Sony Ericsson's styling is consistent, and the K800i will hold no fears for anyone who's used a previous candybar. It's slightly heavier (115g) and taller than its impressive K750i predecessor, partly to make room for a large 2-inch screen and partly to accommodate the extra 3G technology.

The love it or hate it five-way joystick remains at the heart of the interface. I find it spongy and imprecise but some users swear by (rather than at) it. Menus are fast, sharp and colourful on the 240x320-pixel, 242,000- colour display. Voice and video calling (there's a tiny secondary lens above the screen) are quick and simple, although the audio quality isn't stunning.

The camera is activated either by pressing the side-mounted shutter button or moving a flimsy plastic lens cover. This slides far too easily, flipping you out of photo mode at the slightest excuse, and adds an unwelcome extra millimetre to the Cyber-shot's waistline. Previous handsets didn't need one and it's hard to see the logic for it here.

Not the brightest

The landscape-format screen is sharp but not especially bright or responsive, and fades swiftly to black in low light. There are lots of camera features, including macro/infinity focus presets, spot-metering, white balancing and scene modes.

Drive options include the useful BestPic (which shoots nine images for you to choose the best) and an in-camera Panorama mode that's fun but delivers only sub-megapixel files.

The built-in flash is even, powerful and has optional red-eye reduction. However, while autofocusing is efficient outdoors, it doesn't always integrate well with the flash. If the blinding red AF assist lamp fails, you end up with blurred, washed out images. When it does work, night portraits are amazing - a world away from grainy, dull snaps common with LED lights.

The K800i chooses its own sensitivity, from 80 to 400. At ISO 80 colours are bright and natural, while ISO400 shots show a softness. Enlarge images fully and you'll see optical distortion and occasional jagged edges.

Other useful features include a decent media player with support for the latest A2DP stereo Bluetooth headsets, a RSS newsreader for blog feeds and good battery life. Sony needs another memory card format like it needs further delays to the PlayStation 3, but sure enough here's a slot for the miniscule new MS Micro (aka M2).

You'll have to buy your own, as there's none in the box - just 64Mb of internal memory. Don't be fooled by the Cyber-shot branding: this is still a phone with a camera attached rather than the other way around.

But if you want convenient and capable photography at all hours of the day and night, on top of an excellent all-round phone, the K800i makes for a stunning combination.