Find Out Whether This Unkillable Tracker Is On Your Smartphone

"“The most objectionable part is that it’s a boneheaded technical design, no matter what you think about carrier selling information about you,” says Mayer. “In the mobile space, it’s particularly hard to track people, but they’ve implemented the ultimate cookie. Any website can use their technology to follow you, even if you clear your cookies. There’s nothing you can do short of a VPN.”"