Symbian is going downmarket - aiming the next version of its mobile operating system at the high-volume, low-cost mass market.

Version 9.0 will appear in phones in the second half of the year, with a greater emphasis on security, Symbian said. Intel is building hardware specially for it, which should simplify phone manufacturers' jobs.

Extra battery life and multimedia performance should also come out of the new designs, Symbian said, thanks in part to a new compiler from Arm, the developer of the StrongArm chips on which Symbian OS runs.

Version 9 will prevent applications from sending text messages, making calls or accessing personal information unless specific permission has been granted. Symbian's image has been tarnished recently by reports of Trojan horses such as Gavno that affect phones running its OS.

Symbian is also creating a digital signature programme for authorised app developers to help raise doubts in users' minds before they agree to install third-party software on their phones - the method by which virus and worms usually get onto phones.

Symbian 9 also includes support for Bluetooth stereo headphones, and the addition of audio mixing and playback functions - all of which should appeal to music fans - as well as the latest copy prevention systems for commercial music files, which should appease the record labels.

The software also gives network operators or employers more remote control. Symbian 8 introduced over-the-air control of device settings, but the latest version adds support for other management functions, including the ability to remotely examine which applications are running on it and how they are configured - even to install new applications.

A digital certificate stored in the phone is first used to authenticate the identity of anyone seeking remote access, then the user is asked whether they wish to grant permission to the remote visitor to enter.

For business users, the new software also offers improved e-mail, including the ability to accept meeting invitations sent by colleagues using applications such as Lotus Notes or Outlook. It also adds support for Java Community Process standards for personal information management.