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By next summer, most new smartphones may no longer be quite so attractive to thieves.

Microsoft and Google said Thursday that phones using their operating systems — including handsets produced by big names like Samsung, Nokia and Motorola — will have a so-called kill switch that can render the devices unusable after they have been reported stolen. Apple’s iPhone has had a kill switch, called Activation Lock, since September.

The plans for additional security measures come on the heels of new data in New York, San Francisco and London that law enforcement officials believe supports their long-held belief that a kill switch will make smartphones less appealing to thieves, particularly those who intend to resell them on organized black markets.

Comparing data in the six months before and after Apple released its anti-theft feature, police said iPhone robberies in San Francisco dropped 38 percent. In London, they fell 24 percent.

In New York City, robberies (which typically involve a threat of violence) of Apple products dropped 19 percent and grand larcenies of Apple products dropped 29 percent in the first five months of 2014, compared with the same time period from 2013, according to a report from the New York attorney general’s office, which included data from the New York City Police Department. By comparison, thefts of Samsung products increased 51 percent in the first five months of 2014, compared with the same period a year ago, the report said.

Samsung introduced a kill switch for its Galaxy S5 device in April, so it will be some time until its effect on theft rates can be evaluated.

A kill switch is software that lets consumers lock down a phone after the device has been reported stolen; users can reactivate the phone only with the correct password or personal identification number. That makes it difficult to sell on the black market.

“The introduction of kill switches has clearly had an effect on the conduct of smartphone thieves,” Eric T. Schneiderman, New York’s attorney general, said in an interview. “If these can be canceled like the equivalent of canceling a credit card, these are going to be the equivalent of stealing a paperweight.”

Over the last year, lawmakers across the country have pushed for stronger anti-theft features on smartphones. In May, Minnesota became the first state to require a kill switch on all smartphones sold there. In California last month, senators passed a bill requiring phones sold in the state to include the anti-theft technology. That bill still requires approval from the governor of California, Jerry Brown.

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Earlier this year, over a dozen companies, including Apple, AT&T, Google, Samsung Electronics and Verizon Wireless, committed to offering free anti-theft software for cellphones by summer of next year.

Microsoft said that it would introduce a kill switch in a future software update for its Windows Phone operating system. Google will also be introducing one in the next version of Android, said Matt Kallman, a Google spokesman. Combined with Apple’s iOS, these three operating systems control 97 percent of the smartphone market, according to comScore.

Other factors could have contributed to the decrease in iPhone thefts. Police and tech companies have tried harder over the last year to educate consumers on additional security measures to protect phones, like setting up passcodes, which can make it harder to gain access to devices so that they can be erased and resold.

In a statement, Apple said that its kill switch software, Activation Lock, was aimed at preventing unauthorized access to users’ iPhones and iPads. Apple also said that Find My iPhone, a software feature for tracking lost or stolen Apple devices, has been available since 2009.

“Apple has led the industry in helping customers protect their lost or stolen devices,” said Trudy Muller, an Apple spokeswoman. She said Activation Lock “can help you keep your device secure, even if it is in the wrong hands, and can improve your chances of recovering it.”

Samsung said in a statement that it would continue to work closely with the carriers, Mr. Schneiderman and George Gascón, San Francisco’s district attorney, toward preventing phone theft.

The CTIA, a trade organization for the wireless industry, had been resistant to calls for legally requiring kill switches. But Jamie Hastings, vice president of external and state affairs for CTIA, said Thursday that the group was helping solve the problem of phone theft by offering resources that educate consumers.

For example, it created a website, beforeyouloseit.org, that has information about anti-theft apps people can install. “We remain committed to helping law enforcement and consumers deter smartphone thefts,” Ms. Hastings said.

Mr. Gascón has been one of the most vocal supporters of a kill switch. He and Mr. Schneiderman collaborated to form the Secure Our Smartphones initiative to press businesses to create a technical way to dissuade thieves from stealing phones.

Mr. Gascón said plenty of work remained. He said he hoped all manufacturers would include a kill switch turned on by default on all smartphones so consumers did not have to figure out how to use it. In the iPhone, for example, it is not turned on by default.

“Many consumers might not be tech-savvy enough to do this,” Mr. Gascón said. He added that he still thought it was necessary for there to be laws requiring kill switches in phones, similar to how seatbelts eventually became legally required inside cars.