Microsoft and phone maker Sendo will tomorrow demonstrate their next generation mobile internet access phone device, which should be in the shops before the end of this year.

If 'mobile internet access and phone devices' seems like a mouthful, wait until you start deciphering the acronyms. But essentially companies such as Symbian, maker of the Epoc operating system for phones and PDAs, have a threat on their hands.

Tomorrow Sendo will be showing off a prototype of its Z100 smartphone at the GSM World Congress in Cannes. The device has a colour display and uses Microsoft's software platform for such devices, code-named Stinger.

The phone will use the so-called '2.5G' system called GPRS (general packet radio service), which doesn't have nearly the bandwidth of 3G systems, due to be rolled out before 2005.

According to Microsoft, Sendo's Z100 weighs a mere 99g, which makes the prototype smaller and lighter than GPRS phones currently on the market. Admittedly there are hardly any of those, and the first analogue and then GSM phones were bricks until companies brought sizes down through development.

It's been reported the phones will be priced at around $800 (~£550), but this initial price is sure to drop. This of course depends on economies of scale – if people buy into GPRS phones, this could be the handheld device of the future.

Microsoft last year announced an agreement with Samsung to produce Stinger-equipped mobile phones. Samsung will demonstrate a phone running Stinger at the mobile phone conference, Microsoft said.