By Jo Twist BBC News Online technology reporter

The P900 is sophisticated and robust

But the Sony Ericsson P900, which was unleashed in November, is far sleeker, lighter, slimmer and much more sophisticated looking than its older sister, which looked a bit like a toy.

Black and silver, and in a plastic that looks like metal, the P900 packs in all that its predecessor did, but has left out little niggles that might have let the P800 down.

For a smartphone, it lives up to its name in more ways than one.

All in one

The operating system is of the UIQ Symbian (v.2.1) variety, but some might find it is not intuitive enough for their liking.

Users can choose from an application list or, if preferred, use colourful icons to represent the applications.

As a smartphone it has all the usual and useful features which offer business and non-business users a variety of PDA-type functions.

These include camera, MP3 player, browser, voice recorder, Bluetooth, GPRS/Wap, calendar and diary functions, and SMS/MMS. It also comes with a 32Mb memory stick card.

P900 SPECIFICATIONS WAP 2.0 SMS/MMS/e-mail 16 hours' talk/20 days' standby Polyphonic and MP3 ringtones Tri-band/ Bluetooth Handwriting recognition Backlight display Video streaming Processor speed 153 MHz 16Mb internal memory Display type TFT LCD Memory Stick Duo expansion slot Dimensions (WxDxH) 5.7 x 2.4 x 11.5cm Weight 150g Symbian OS 7.0, UIQ 2.1

It arrives with a lot of software and useful applications already on the phone, like a file manager application, colourful themes, and World Mate which gives users on the move real-time information on currencies, times and the weather.

Users can quickly get around different applications using a combination of the jog dial scroll button housed by your thumb on the left of the phone, and the stylus, which is snugly hidden in the phone on the right.

This allows for one-handed navigation action as well as two-handed trickery to dazzle friends and colleagues.

The phone comes with a flip which users can remove, but the backlight on the keypad of the flip is a cool-ice blue which impresses in the dark.

Ultra-organised users can also easily synchronise contacts, Outlook e-mails, notes with their PCs over Bluetooth, infrared or via the saucer-like USB cradle.

Multimedia messaging is made fairly straightforward. When putting together a truly multimedia with voice, animation and text, the user is helped along with option tabs at the bottom of the message.

A nice little touch is the addition of instant message-like emoticons, saving users the effort - albeit very little effort anyway - of tapping them out manually.

Blinding screen

The clarity of the touch screen display is one of the most impressive features of this phone however.

It is far superior to the P800 display, and offers a sharpness that is full of far more colours, 65,536 (16-bit) to be precise.

At 320x208 pixels, the screen is large enough to allow easy navigation and picture viewing, and turning it horizontally allows widescreen game action.

The web browser allows surfers to view pages in full-screen mode, another little bonus which helps.

But it is perhaps the camera function will could provide the most fun.

The camera and display quality are very good

It shoots snaps with the VGA (640x480) resolution digital camera in 24-bit colour, but also takes MPEG-4 video with sound. The length of clips depends on how much memory you have.

In a sign that perhaps camera phones could challenge digital cameras in the future, there are various options to help picture quality in different light conditions, including indoor, outdoor and night.

Users can then personalise their phone in the usual way with pretty high-quality - if not a little cheesy - holiday snaps as wallpaper. Annotating them with the jotter function just adds some mischief to the mix.

Finally, it is a joy to no longer type text messages. Graffiti means handwriting is recognised without having to learn an entirely different language.

Although old-school texters still do have the option to text with the keypad either in the virtual or actual flip mode, using T9 predictive text.

Overall, smartphone users would be delighted to see this little package in their Christmas stockings.

Although not a vast improvement for P800 owners, it is much better looking and much more niggle-free than its sister. But the improvements do not really justify the upgrade unless you have an understanding bank manager.

For those who have been saving their pennies for the phone that does everything you need for business, mischief and leisure, but is not overly complex, it is a great choice.