Socket Mobile is preparing to fill the gap in the handheld market left by the withdrawal of other vendors such as Dell. The company believes there is a need for a business-focussed mobile client to sit between costly fully-rugged handhelds and converged devices aimed mostly at consumers.

In June, Socket will ship its SoMo 650 handheld, a high-end device based on a 624MHz Intel XScale processor with 128MB RAM and 256MB Flash memory, running Windows Mobile 5.0. The firm said the SoMo will be supported for three to five years, in contrast to consumer devices with more rapid replacement cycles.

"This been a problem for firms, because it can take up to 18 months to plan and develop a mobile solution, then when you get to the deployment stage, you find the device has been discontinued," said Socket chief executive Kevin Mills.

The SoMo, which is expected to sell for about £400, is less costly than rugged PDAs from Motorola's Symbol arm or Intermec but has more enterprise-friendly features than low-cost devices. It ships with a Wi-Fi roaming client supporting hand-off between access points, for example, and its firmware includes drivers for Socket peripherals such as barcode scanners.

"Business customers are looking for more than a consumer-grade device can offer, because workers might be pushing the buttons all the time. However, if you get a Symbol, people have to accept a bulkier, more feature-rich device than they want," Mills said.

The SoMo is aimed at applications such as inventory control, sales force automation and patient tracking in the healthcare industry.

Later this year Socket will release management tools for the SoMo 650, including a mechanism to let customers deploy updates to its operating system and applications. A tool called DeviceGuard is also planned that lets firms control what applications end users can run on the device.

Mills said that Socket was already seeing interest from companies currently using Dell's Axim handhelds.

"Dell's leaving a vacuum in the market. We will get some sales out of that, although a lot of customers won't be deploying for about a year," he said.

The SoMo 650 weighs 178g and has a 320 x 240 3.5in display comparable to many Pocket PC handhelds. It ships with a 1200mAh battery as standard, but an optional 2600mAh extended battery offers longer life. Expansion is via CompactFlash and SD Slots, which are reinforced against damage.