Smartphones may have taken a while to gain momentum, but they're now arriving thick and fast. The latest to hit the market is Sony Ericsson's Symbian-based P900, which is an update to the popular P800. Physically, the new model is very similar in size and weight to its predecessor - larger than your average phone, but smaller than a PDA.

The main difference is the flip keypad, which now has wired buttons rather than rubber feet that push through to the touch-screen. This makes it easier to use and means problems are less likely to develop.

With the flip closed, the P900 acts just like an ordinary tri-band mobile phone, and has an intuitive interface. Open the flip and the full 208 x 320 65K screen springs to life, displaying the PDA interface, which you can use with the provided stylus or the scroll-wheel on the side of the phone.

Shortcut icons give you access to all the usual options - diary, address book, memos and text messages, while a separate menu button gives you access to all the other applications installed. It's simple to use and caused us no problems.

There's 48MB of Flash memory of which 16MB is available to the user, while Sony Ericsson also provides a 32MB Memory Stick Duo to give a more reasonable 48MB. You might find that you want to upgrade this, especially if you are going to play MP3s or take a lot of photos using the camera.

The P900 connects to a PC via a USB cradle to synchronise data, however, the P900 balances rather precariously and it's easy to knock over.

As smartphones go, the P900 is one of the best of the bunch, perfectly balancing on the delicate edge between phones and PDAs.

Contact: Sony Ericsson 08705 237 237
www.sonyericsson.com/uk/

Specifications:

• Tri-band mobile
• 48MB of Ram (16MB free for the user)
• Memory Stick Duo slot
• Bluetooth
• Infra-red
• 208 x 320 screen
• 153MHz ARM
• 57 x 24 x 115 (w x d x h mm)
• 157g