This weekend, Apple began rejecting mobile applications from the App Store which retrieve the end user’s IDFA (Identifier for Advertisers), but don’t show any ads. The IDFA is today the preferred ad tracking option, following the phasing out of the unique identifier known as the UDID. Over the years since Apple first announced its intention to end developers’ reliance on the UDID, due to privacy concerns and a changing regulatory environment, Apple had been pushing app publishers to adopt the IDFA instead.
Throughout 2013, Apple signaled to developers it was time to make the switch by rejecting apps using cookie-tracking methods, and later those using MAC address tracking, for example.
But now that a large number of publishers have moved over to IDFA, Apple is beginning to inform them of how the IDFA can and can’t be used. The clause in particular which Apple is enforcing is 3.3.12: