The introduction of the Activation Lock feature in Apple's iOS 7 software has dramatically reduced the number of iPhone thefts in the last few months, police on both sides of the Atlantic have claimed.

The improved Find My iPhone tool, added last year, acts as a virtual kill switch as it prevents unauthorised users from erasing and reactivating the device without the owner's Apple ID and password.

As a result, the device becomes all-but-useless to thieves, who are snatching iPhones in much fewer numbers compared with six months ago.

The New York Times brings word from London police that iPhone thefts are down 24 per cent, while they've dropped 38 per cent in Apple's San Francisco homeland.

Paperweight

New York Attorney General Eric T. Schneiderman said the so-called kill switch meant all thieves were getting for their criminal endeavours was a very elaborate, unsellable 'paperweight.'

The Activation Lock feature is automatically enabled when users choose to set-up the Find My iPhone GPS tracking tool, when setting up new iOS devices for the first time.

As well as preventing third parties from wiping and reactivating the device, Activation Lock also prevents Find My iPhone from being turned off and stops anyone signing out of iCloud on your device.

Lawmakers in Minnesota and California have recently passed bills requiring all smartphones to have anti-theft technology, while a national smartphone kill switch bill was tabled in February. Last year London Mayor Boris Johnson also urged smartphone manufacturers and software developers to do more to protect customers from theft.