Recent research from analyst firm IDC says that the arrival of mobile phones incorporating hard drives will "require a number of further evolutionary steps" before such technology is good for consumers.

"The addition of HDD storage will eventually address many of the limitations that have kept converged devices from reaching their full potential," said Alex Slawsby, senior research analyst in IDC's Mobile Devices service.

"Handsets already have the killer application of wireless telephony, and adding increased storage will make them a viable option for extensive music, imaging, reference, and business applications."

The report looks at the potential for the emergence of hard drive equipped devices, but warns: "Cost, size and power consumption are prohibitive factors… Flash memory is still the best near-term option with rotating storage solutions too costly, too large and too power hungry for all but the highest end phones."

The report adds: "Increased wireless network bandwidth (3G networks) will continue to drive the need for additional storage capacity on mobile devices."

On an Apple-related topic, the analysts say: "In 2003, 1.8-inch drives (as used in iPods and other music players) represented a mere 1 per cent of all hard drives shipped worldwide and the 1-inch drive represented just 0.1 per cent."