Demands: Boris Johnson, the Mayor of London, is among politicians pushing all phone manufacturers to tackle phone theft

An Apple ID and password are also required to turn off the new 'Find My Phone' application--which tracks a stolen or lost phone's GPS location. A custom message, such as 'This iPhone is lost. Please callme' will be continuously displayed even if thieves manage to erase the phone. 'We think this is going to be a really powerful theft deterrent,' Apple's senior vicepresident of software engineering Craig Federighi said at the developer's conference . Police warn that criminals wantmobile phones, iPads and other electronic devices to sell on the black market overseas, where handsets can be sold on for twice their value in the UK. And they say the public are leaving themselves vulnerable to attack by texting or using the internet while walking along, often withearphones in, oblivious to what is going on around them. The Office for National Statistics said the number of personal thefts increased by eight per cent last year. In theyear to December 2012 police recorded 107,471 such offences up from 99,396 a year earlier. The true total is likely to be much higher as many people do not report incidents to the police. An ONS spokesman said: ‘This represents a speeding-up of the recent increases seen for this offence. ‘Anecdotal evidence suggests that this may be in part drivenby theft of smartphones including the phenomena of bike riders stealing phones from people’s hands.’