Fresh from its all-conquering Chocolate phone, LG has obviously had its taste buds tickled for world domination. Its latest target is the music mobile market.

Not deterred by the fact that Sony Ericsson appears to be heavily targeting this particular sector with its Walkman line-up, LG has stormed in with a 3G-toting slider that shares the same DNA as the Chocolate - but will it share the same success?

Looks wise, the 3-exclusive U400 is a bit like the Chocolate's beefier (yet not unattractive) older brother. The glossy black body and hidden LCD remain, but where the Chocolate was all about understated simplicity, the U400's not averse to including the odd bit of extroverted styling.

In a cunning move to steal the market from under the nose of Apple's iPod, LG has included its own version of that most ubiquitous of iPod characteristics - the click wheel (which, to avoid any legal wrangling, we'll call the jog wheel from now on).

Located below the 2in QVGA screen, the blue-trimmed jog wheel is used to scroll through menu options, cleverly displayed onscreen in a graphical representation of the wheel. Those yet to come round to the jog wheel-only way of doing things will be relieved to hear the wheel doubles as a five-way joypad, while the menu can also be set to display in a more traditional grid format.

On closer inspection, the wheel's blue trim is made up of two soft-key options on either side for accessing the 3 music store and the network's mobile internet portal, Planet 3, and a Menu button at the bottom.

Separate Call, Cancel and End buttons are located to the right of the jog wheel, while a quick access key activating the camera can be found on the silver edging of the handset. Also located here are the volume control buttons, a quick link to download music tracks, a microSD card slot (complete with 512MB card) and the headphone port.

Features

LG has gone for broke with the U400, giving it 3G capabilities in a compact package - not to mention it's the company's first UK handset to boast a 2-megapixel camera. However, this phone is quite clearly aimed at the upwardly mobile (no pun intended) music fan, so we'll concentrate on the phone's musical prowess first and foremost.

Linking up once again with 3 gives LG the chance to tap in on the network's download service. One click on the left soft-key opens the Java-powered 3 Player, which gives the user full licence to play songs or browse the 3 music store for over-the-air full-track downloads.

Getting tracks from your PC's library is also easy, thanks to the bundled My DJ software and USB connectivity. MP3, AAC, AAC and WMA fi le formats are all catered for.

Unless you enjoy irritating people on public transport by playing music through your phone's speaker, you'll probably find yourself using the supplied stereo headphones. Plugging into an attachment containing a full-functioned remote, these headphones demonstrate remarkably good build quality and styling.

If you'd prefer to plug in your existing cans, the 3.5mm port in the remote attachment leaves you free to change your choice of headgear. Better still, A2DP compatibility means you can dispense with wires altogether in favour of the latest range in stereo Bluetooth headsets.

Aside from the music player, an embedded DJ app transforms the jog wheel into a turntable, allowing you to jazz up tracks with a bit of improvised scratching and additional percussion, while a Music Composer puts individual ringtones within your reach.

The latter has a whopping 31 styles and 10 instruments to choose from (with an adjustable metronome for the more professional), so there really is no excuse to make do with just 'ring ring'.

Plenty of settings

Of course, there's more than music to this phone, and LG has done its best to widen its appeal by including a 2-megapixel camera complete with a tiny secondary VGA camera on the front for face-to-face video calling.

There are plenty of settings on offer to adjust things like the brightness, white balance and quality of both snapshots and video clips, and there's also a fl ash and Night mode for darker shots. However, a notable absentee is an auto focus facility.

Video is recorded and viewed in MPEG4 format, with eight lengths of shooting duration offered between ten seconds to an hour. There's also a specific setting for video intended to be sent as part of an MMS message.

Aside from these big hitters, all the other usual suspects are here in force. Hidden amongst the menus are a host of features aimed at helping you keep your life in order, including a calendar, to-do list, memo section (which can be pin-protected for private types) and alarm clock.

Messaging options incorporate SMS, MMS and an email client. Indeed all in all, there's enough to keep you occupied for some time (unless you're into games, in which case you'll have to get downloading!).

Performance

As a first serious foray into the world of music mobiles, LG has turned in an impressive performance. The build-quality and functionality of the handset is top-notch, and the menu is thoughtfully laid out. That said, the placing of the soft-keys is slightly deceptive, and it was hard to tame our thumbs from hovering towards the more logically positioned Call button to select options.

While the handset may not be quite as polished as Sony Ericsson's Walkman range, it certainly benefits from 3's expertise in the music arena. The supplied software is easy to use, and there's plenty of music-orientated wizardry to keep your ears - and fingers - entertained.

It's also good to see a variety of headsets catered for thanks to the inclusion of a 3.5mm headphone jack and A2DP compatibility, although the bundled set does the job more than adequately.

Slightly more disappointing was the camera lens, which although a 2-megapixel affair suffered from the absence of an auto focus. Colour rendition was accurate and vibrant, but edges were sometimes a little fuzzy.

Not forgetting the U400 also has to act as a mobile phone, call quality was extremely good and suffered no dropouts during use, with all calls clear at both ends. Video calling, too, was of reasonable quality in terms of sound and vision, and for a 3G handset it weighed in with a good battery performance, lasting nearly five days under standard use.

The U400 is an impressive musical debut, and combined with LG's willingness to innovate and push boundaries will help cement the company's reputation as one to watch. Miriam Brent

Jog wheel: The U400 uses a handy if not altogether intuitive jog wheel dial for track selection and menu control

Memory card slot: Easy to swap in and out of the phone, the microSD card slot sits on the side of the handset

Camera: A decent 2-megapixel camera is on the back of the phone, which can be used with the slider open or shut

Slider: The neat keypad is revealed by pushing up the smooth slide-action fascia of the phone