Full-length feature films for viewing on a mobile phone become available this month with the launch of a new technology from UK company Rok Entertainment.

They come on a £14.99 Multimedia Card (MMC), which is compatible with SD (Secure Digital) slots and includes a Rok media player that formats the film for the phone screen.

Cards will come in 128MB and 64Mb capacities and Rok marketing director Bruce Renny says there will be 'a little space left' for private use.

'The price is a little higher than a DVD but that reflects the cost of the Multimedia Card,' he said.

You will not be able to save money by swapping films on the card. 'Film companies want to be sure that their property is safe,' said Renny.

The cards will be available initially only for Symbian-based phones such as the Nokia 7710 or the Siemens SX1, but other platforms will be supported shortly.

Deals announced by Rok reflect content light enough to be tolerable on a tiny phone screen: it has signed up Aadrman Studios, creators of Wallace and Gromit; Indestructible Studios, which owns Captain Scarlet; and hit TV shows such as Red Dwarf.

Rok faces competition from dedicated portable players that can play recorded content. And new affordable 1GB SD cards - Transcend has just announced one costing around £78 - could also encourage viewing of recorded content on mobiles.

The question for device makers is whether video use will popularise products with larger screens, with tiny phones giving way to phone-enabled PDAs.