Phones allow coordination and convenience. But as politicians in many countries learned several years ago, they allow surveillance. Security isn’t just a concern in Middle East autocracies, or for would-be revolutionaries. Mobile phone surveillance, for example, is tough to escape for cellphone users anywhere, said Ethan Zuckerman, senior researcher at the Berkman Center for Internet and Society at Harvard Law School, and a founder of Global Voices, a worldwide group of bloggers and interpreters that has produced similarly themed guides. Mr.