Facebook Solves the Global Cookie Shortage

http://www.bloomberg.com/news/articles/2015-04-16/facebook-tracks-app-users-across-devices-to-prove-ads-work

Enter Facebook, which promises the more than 1 million businesses that advertise through its Atlas Solutions network that they can follow 1.4 billion users from PCs to smartphones to tablets and back. To use Facebook, you have to log in, and the social network records identifying information about each device you’ve logged in from. That data is stored in your profile, so Facebook knows it’s you online, even when you’re visiting other sites…