According to The Wall Street Journal, Apple will soon be releasing a new system to let developers know who's using their iOS apps. Anonymous sources have said that the company hopes this system will help app builders gather analytics while doing a better job of protecting user privacy. Unfortunately, none of the people interviewed seem sure how such a system would work. The most specific source said that Apple would "likely rely on a sequence of numbers that isn't tied to a specific device." Ideally, developers could identify individual users on an app, but no one could collate the data to tell who it belonged to.
Whatever the technology, it would replace the more common Unique Device Identifier or UDID, which is often used to track user behavior. The UDID is a permanent identifier, and critics have said analytic data combined with this kind of single code could be used to find personal information on individuals. Apple has also clashed with analytics companies in the past, after Flurry collected data about prototype hardware. The company deprecated the UDID in iOS 5 last year, and earlier in 2012 we started hearing about "blanket rejections of apps that use UDIDs." If Apple is planning to release something, we expect we'll hear more about it at WWDC.