Top prosecutors in San Francisco and New York say they are bringing in state and federal security experts to test the latest anti-theft features designed to stop the surge of stolen smartphones in the U.S., Mercury News reports.

Apple’s iPhone 5’s activation lock and Samsung’s Galaxy S4 with Lojack for Android are the two phones being tested.

According to San Francisco District Attorney George Gascon, the experts will treat the phones as if they were stolen and try circumventing the anti-theft features to draw their own conclusions regarding their effectiveness, the article reports.

Almost one in three robberies nationwide involves the theft of a mobile phone, according to the Federal Communication Commission, which is coordinating the formation this fall of a national database system to track mobile phones reported stolen.