Smartphones become indispensable tools for journalists, human right workers, and activists in war-torn regions. But at the same time, as Intercept points out, they become especially potent tracking devices that can put users in mortal danger by leaking their location . To address the problem, NSA whistleblower Edward Snowden and hardware hacker Andrew "Bunnie" Huang have been developing a way for potentially imperiled smartphone users to monitor whether their devices are making any potentially compromising radio transmissions. "We have to ensure that journalists can investigate and find the truth, even in areas where governments prefer they don't," Snowden told Intercept. "It's basically to make the phone work for you, how you want it, when you want it, but only when." Snowden and Huang presented their findings in a talk at MIT Media Lab's Forbidden Research event Thursday, and published a detailed paper . From the Intercept article:Fortunately, a smartphone can be made to lie about the state of its radios. The article adds:Wired has a detailed report on this , too.