A Personal Digital Assistant is an essential replacement for your 80s filofax. We saw Palm Pilots and Psions dominating the field, but now Microsoft Windows CE devices are muscling in. The HP Jornada 430se runs Windows CE 2.11 which, unlike its predecessors, is colour. It also has multimedia capabilities such as voice recording using the built-in microphone.

This, of course, is nothing new in the PDA world, so the 430 has another trick up its sleeve - it can play MP3s. With only 16Mb of RAM, however, it's going to be difficult to fit any more than one or two MP3 files (at CD quality) onto the 430se, as this memory is shared between storage and RAM. The question we want to ask HP, and other maufacturers of colour PDAs, is whether all this functionality is really necessary in a personal organiser.

One of the first colour Windows CE PDAs was the HP Jornada 420. This only had a 256-colour display, compared with the 430se which has a 65,536-colour display and 240 x 320 pixels. The 430 also has a faster 133MHz Hitachi processor, compared with 100MHz, which in conjunction with the colour LCD means the proprietary Li-Ion battery lasts about seven hours.

The 430 also boasts stereo audio output via its headphone jack and the bundled in-the-ear headphones. The standard bundled software includes an MP3 player, Pocket Outlook, an image viewer, a voice recorder, EzExplorer and five original HP applications for even more functionality. Outlook lets you manage your appointments, tasks, contacts and Inbox. The full version of Outlook 2000 is included on CD.

The Jornada 430 shares the same physical dimensions as the 420, but gone is the blue case, replaced by a more serious grey affair. A clear cover protects the screen and flips back to allow input on the Jornada's touch-screen via the standard CIC Jot character recogniser or tiny on-screen keyboard. There are four control buttons on the side, as well as quick-launch buttons at the bottom of the screen.

We found that even with a 133MHz processor, some processes still took a long time. The 'reappearance' of the hour glass for simple operations like closing an application reminded us of old 386 PCs. And athough we felt that colour was unnecessary on a PDA, the display was very clear indoors. Outside in sunlight it was simply unusable - we just couldn't see it. Really, the 430 is aimed at mobile professionals who spend a fair amount of time away from their desk. It represents a large improvement over the original Jornada 420, and has the edge over other colour Windows CE devices due to its ease of use and compact dimensions. We liked the MP3 functionality, and you can add a Type I or II CompactFlash card in the slot - a 340Mb IBM MicroDrive, for instance, which would let you store eight hours of CD-quality MP3 music.

Disappointingly, with all this functionality, you don't get Pocket Word or Excel - a shame when the 430 is aimed more at corporate users than consumers.