By setting up a grid of these location-based ads, the adversary can track the target's movements if he or she has opened an app and remains in a location long enough for an ad to be served—typically about four minutes, the team found.
Importantly, the target does not have to click on or engage with the ad—the purchaser can see where ads are being served and use that information to track the target through space.
"We did this research to better understand the privacy risks with online advertising.
"To be very honest, I was shocked at how effective this was," said co-author Tadayoshi Kohno, an Allen School professor who has studied security vulnerabilities in products ranging from automobiles to medical devices.
In fact, the other countries in this region also have low sex ratios. As is the case with most online dating sites, you will at times come across sketchy or fake profiles.