Sony is adding colour to its newest Clié PDA (personal digital assistant), at least in Japan.

With today's Japanese launch of the Clié PEG-T400, a sleek new model that was launched in the US last month under the name PEG-T415, the company also announced a colour version, the PEG-T600.

Also new is a digital still camera card, announced last month in the US, and a GPS (global positioning system) card, which Sony is announcing for the first time anywhere.

Features of both devices are similar, with the display, which can show 65,536 colours, and the memory, which at 16MB is double that of the monochrome model, being the only main differences. The addition of the colour display comes at the price of thickness and weight. The T600 is 12.5mm thick, compared to the 9.9mm T400, and weighs 138g, compared to 122g for the monochrome model.

All other features are the same. It has a 33MHz Dragonball VZ processor, runs Version 4.1 of the Palm operating system and has a screen resolution of 320x320. Battery life of the internal lithium-ion cell is given as 12 days, assuming daily use of 30 minutes per day, according to Sony.

The two new modules plug into the Memory Stick slot on each Clié handheld. The digital still camera module has a low-resolution 100,000 pixel CCD (charge coupled device) image sensor capable of delivering an image up to 320x240, or a quarter that of VGA (video graphics array) quality.

The second new module receives signals from GPS satellites and is able to provide the user with their location to within a few tens of meters accuracy. Such devices are often combined with mapping software applications to give users a map of the immediate area around them.

Both PDAs and the camera and GPS cards will go on sale in Japan on 8 December. The colour model will retail for around £230, the monochrome model will cost around £172, the digital camera model will be around £87 and the GPS module will cost £115, said the company. All prices exclude tax.

Sony had no word on when the colour model will be available outside of Japan.