Apple explains how Advertising Identifier, replacing UDID in iOS 6

Apple no longer wants developers UDID’s use banners and to monitor the use of apps. In iOS 6 the UDID (unique code linked to your iOS device) will no longer be used for such applications. Instead, advertisers can use a new Advertising Identifier. This is not linked to any personal information and is also not permanent.

There are similar Developer Identifier that are not yet published. Advertisers still can with the Advertising Identifier to track how many times a specific ad is shown for example and if it is clicked, but it is no longer linked to personal information. The user can also turn off, as shown in the figure above shows.

All ad networks should in future use the Advertising Identifiers, but the transition will be gradual. It might happen in the next few months old ways to track ad networks. Apple no longer wants using the UDID, because as gaming networks like OpenFeint which opens Facebook profile coupled with your UDID. This is also the name, residence and work and other personal data to be retrieved. Later proved many other gaming networks also UDID’s to personal link. Recently leaked a file with more than 1 million UDID data from hackers through organization AntiSec. Initially they would come from the FBI.