The potential for mobile phone monitoring was highlighted last week by Symantec, the information security company. It warned mobile phones are potentially vulnerable to spyware, software that covertly gathers a user's information without their knowledge. These could enable snoopers to remotely activate a mobile phone's microphone, take pictures with its camera or record conversations without the user's knowledge.

Such technology might prove tempting to bosses who want to keep track of their employees or journalists hunting stories about celebrities, though the Data Protection Act states a person must not 'knowingly or recklessly' and without consent obtain or disclose personal data.

Industry experts warned that the increasing complexity of phones has its downsides. Richard Starnes said: 'As mobile phones progress, they are becoming the de facto computers of 10 years ago. With these capabilities come vulnerabilities: security is inversely proportionate to functionality. It will definitely be an increasing threat in the coming years.