FILE – In this Tuesday, Jan. 15, 2013, file photo, Facebook CEO Mark Zuckerberg speaks at Facebook headquarters in Menlo Park, Calif. Facebook remains the most used social media site among American teens ages 13 to 17, according to a new study from the Pew Research Center. And, surprisingly, boys visit the site more often than girls. Aided hugely by smartphones and other mobile devices, 71 percent of teens surveyed said they use Facebook, with the same percentage saying they use more than one social network of seven options they were asked about. (AP Photo/Jeff Chiu, File)