Study Shows Many iPhone Apps Defy Apple’s Privacy Advice

In 2011, Apple advised that iPhone and iPad apps should stop logging the unique identifiers of users’ devices, a practice that can be exploited to build up profiles for ad-targeting purposes. But a new study by researchers at the University of California, San Diego, suggests that many apps still do so. At the MobiSys conference in Taiwan this week, the researchers will present data gathered from 225,000 apps installed on 90,000 ordinary iPhones. Their analysis shows that between February 2012 and December 2012, 48 percent of those apps accessed the unique device ID, or UDID, of the phone they were installed on.