Global mobile device sales grew by 51 per cent in the last quarter of 2004 compared to the year before, according to analyst firm Canalys.

But growth was found to be uneven; while sales of smartphones and connected data devices including the Blackberry doubled, unconnected PDA sales rose just five per cent for the year.

Nokia increased its market leading position with strong sales for its Symbian products.

"The next clamshell/keyboard device from Nokia is expected shortly and will further strengthen Nokia's push into the mobile enterprise solution segment," said Chris Jones, Canalys director and senior analyst.

"Motorola also had a good quarter. Shipments of its Windows Mobile and Symbian smartphones were particularly strong in EMEA, and we expect to see its numbers increase during 2005 as more products launch."

Symbian's market share increased again during the quarter, with the operating system shipping on 58 per cent of devices sold. Sales from British firm Sendo and Sony Ericsson were credited for driving demand.

Palm is still the US favourite, but limited availability of the Treo range hurt its position in Europe, making it the number two platform.

Research in Motion continued to chase HP for third place, enjoying a sales increase of 249 per cent on last year compared to HP's one per cent growth.