Drawbridge, founded by a former Google data scientist, says it has matched 1.5 billion devices this way, allowing it to deliver mobile ads based on Web sites the person has visited on a computer. If you research a Hawaiian vacation on your work desktop, you could see a Hawaii ad that night on your personal cellphone.
And a bit about how it works:
Drawbridge, which was founded by Kamakshi Sivaramakrishnan, formerly at AdMob, the Google mobile ad network, has partnerships with various online publishers and ad exchanges. These send partners a notification every time a user visits a Web site or mobile app, which is considered an opportunity to show an ad. Drawbridge watches the notifications for behavioral patterns and uses statistical modeling to determine the probability that several devices have the same owner and to assign that person an anonymous identifier.
So if someone regularly checks a news app on a phone in bed each morning, browses the same news site from a laptop in the kitchen, visits from that laptop at an office an hour later and returns that night on a tablet in the same home, Drawbridge concludes that those devices belong to the same person. And if that person shopped for airplane tickets at work, Drawbridge could show that person an airline ad on the tablet that evening.