One of the new features in iOS 6 that Apple has not been talking about is the return of advertisers being able to track user activity.
Back in March iOS user privacy seemed to be taking a positive turn, as Apple cracked down on rejecting apps that accessed the device's Unique Device Identifiers (UDIDs).
With iOS 6, Apple introduced a new Identifier for Advertisers (IDFA) system assigning each device a unique and anonymous number to act like a cookie, keeping track of your app and web habits for the sake of targeted ads.
For advertisers, IDFA is a fantastic innovation, allowing them to not only target ads based on a user's behavior, but also keep score on whether their ads actually lead app downloads or purchases of their services.
However, while an IDFA does not provide advertisers with any of a user's personal information, for many users any amount of ad tracking is an uncomfortable privacy breach.
Opting out isn't so easy
Apple does provide users with a way to opt out of sharing their device's IDFA, but the process is unnecessarily complicated in a number of ways.
To opt out, users can go into their devices Settings and choose the "General" then "About" menu options to find the "Advertising" settings. From there, users will see the confusing "Limit Ad Tracking" option, which is set to be off by default.
When off, the device will not limit ad tracking, or in plain English, it will allow ad tracking. By turning "Limit Ad Tracking" on, users can disable their IDFA number.
Of course, it does not help that this option is hidden in the "General" settings menu, rather than the "Privacy" settings where any sane person would think to put it.
Opting out of the IDFA will not eliminate all ad tracking on iOS, at least not yet. Some apps may still use alternate ad tracking methods, which is why the device setting only says it will limit tracking rather than eliminate it.
Apple says that in the future all apps will be required to use IDFA, allowing users to opt out completely when the shift is made.
Via Business Insider