The 7100v is exclusive to Vodafone

The keyboard is being used in the Blackberry device 7100v, which has just been launched in the UK by Vodafone.

The new design means the 7100v is much slimmer than earlier Blackberry devices and it looks more like rival smartphones.

The Blackberry is a handheld phone and e-mail device which has become ubiquitous among the corporate elite.

But it is far from a mass market product, with just over a million in use around the world, compared with 200 million mobile phones in the US alone.

The people behind the Blackberry, Canadian firm Research in Motion (Rim), say they hope the new design will widen the appeal of the device among more fashion conscious users.

Chunky device

The keyboard on the 7100v has two letters on each of its 20 keys. It uses SureType software and a 35,000-word dictionary to work out what you are typing, rather than usual predictive text system, T9, found on many mobiles.

Other Blackberry devices had a thumb-sized keyboard

Previous models sported a thumb-sized Qwerty keyboard, resulting in a somewhat chunky design.

"Mobile professionals are torn between their need for a device that offers efficient data input capabilities and their desire for a device they can accept as their primary mobile phone," says Kevin Burden, programme manager at analysts IDC.

"While some full Qwerty thumb-boards deliver the input accuracy that professionals need, the market has awaited a keyboard design that is as quick, accurate, and easy to use as Qwerty solutions, but doesn't compromise the phone experience."

The Blackberry became a technology icon in the late 1990s as a tool that delivered e-mail automatically to executives on the move.

But it now faces tough competition from a profusion of rival wireless devices, among them the Sony Ericsson P900 and the Orange SPV C500.

A slightly different version of the Blackberry device, the 7100t, was launched in the US a week ago.