Privacy campaigners scored a win in advance of Apple’s iOS7 release and the announcement that as of the new operating system’s rollout, the tech giant will no longer be accepting apps which use a Unique Device ID (UDID) to identify users’ devices.
What’s the big deal with UDID’s?
Well much like a social security number is the key to much of your personal information your UDID was the key to uniquely identifying your mobile device.
For those that know where to look, the UDID makes it possible to connect what you do across all of the different apps on your iPhone. Because apps include advertisements that come from various companies, this means that those companies could piece together a profile about you from across the different apps that you use, and this profile could be connected with other data that you permit the app to use, like your location.
Just like “targeted” web ads, the UDID on your phone made it easier for advertisers to understand what products or services would be of interest to you and serve you those ads.
What are they replacing it with?
For now it looks like Apple plan to replace UDID’s with two different identifiers: Vendor IDs and Advertising IDs.
Vendor IDs
ID that is identical between apps from the same developer.
Erased with removal of the last app for that Team ID.
Advertising IDs
Unique to the device.
Available to all applications; used for advertising — iAd has converted from UDID for iOS 6 and later.
Reset with “Erase All Content & Settings”.
For the most part, Vendor IDs will allow developers with multiple apps to identify you as the same user across all their apps. This can help developers understand their audience better and provide a better service.
Advertising IDs will still create a unique identifier for the device but unlike the UDID, this can be turned off or reset, just as cookies can be controlled in the browser on your desktop or laptop.
With the announcement of iOS7 earlier this week, Apple took an additional step, which was to turn off another unique identifier — the “MAC Address” that app developers and advertising companies could use instead of the new Advertising ID. By closing this loophole, Apple is taking the good step of forcing these companies to only use a cross-app identifier that users can control.
What remains to be seen is whether the targeting companies will continue to seek ways around Apple’s mandate. Other technologies, like “device fingerprinting,” have been developed to uniquely identify your device outside of Apple’s framework. Whether Apple will crack down on these methods remains to be seen.