Times used to be, having a smartphone in your hand meant someone probably wanted to steal it. And while that may still be true, authorities in San Francisco, New York and London say the number of stolen smartphones has dropped dramatically since manufacturers started including “kill switches” that allow phones to be turned off remotely if they fall into the wrong hands.

In San Francisco, stolen iPhones dropped by 40%, in NYC by 25% and in London, a whopping 50% in the 12 months after Apple added a kill switch to its devices, reports Reuters.

The officials made the announcement together on Tuesday.

“We have made real progress in tackling the smartphone theft epidemic that was affecting many major cities just two years ago,” said London Mayor Boris Johnson.

Along with San Francisco District Attorney George Gascon and New York state Attorney General Eric Schneiderman, Johnson and other officials pressured for new laws mandating the kill switches.

Thefts in California are dropping because even though its kill switch law hasn’t gone into effect yet, some manufacturers have added software-based switches on their devices, Gascon explained.

“The wireless industry continues to roll out sophisticated new features, but preventing their own customers from being the target of a violent crime is the coolest technology they can bring to market,” he said.

Other states are considering similar measures, with Minnesota passing a theft-prevention law last year that goes into effect this summer.

Meanwhile, Apple, Samsung and Google have all added kill switches to their smartphones, with Microsoft planning to release an operating system for its Windows phones that have them this year.

More reading: FCC Releases Massive Study On Mobile Phone Theft, Asks Wireless Companies To Start Making Changes

Smartphone theft drops in London, two U.S. cities as anti-theft ‘kill switches’ installed [Reuters]

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