SAN FRANCISCO — The top prosecutors in San Francisco and New York say they are bringing in state and federal security experts to test the newest anti-theft features designed to thwart the surge of stolen smartphones.

San Francisco District Attorney George Gascon and New York Attorney General Eric Schneiderman announced today the security experts will be in San Francisco to test Apple’s iPhone 5 with its activation lock and Samsung’s Galaxy s4 with Lojack for Android.

Gascon says the experts will treat the phones as if they were stolen and try circumventing its anti-theft features to draw their own conclusions on its effectiveness.

Gascon and Schneiderman met in New York City last month with representatives from Apple, Samsung, Google and Microsoft, urging them to create a “kill switch” to render stolen smartphones inoperable. Almost 1 in 3 robberies nationwide involves the theft of a mobile phone, according to the Federal Communications Commission, which is coordinating the formation this fall of a national database system to track cell phones reported stolen.

“Together, we are working to ensure that the industry embed persistent technology that is effective, ubiquitous and free to consumers in every smartphone introduced to the market by next year,” Gascon and Schneiderman said in a statement.

Nearly 175 million cell phones have been sold in the U.S. in the past year and account for $69 billion in sales, according to research firm IDC.

Lost and stolen phones cost consumers more than $30 billion last year, according to a study.