Why is the deprecation of UDID a good thing?

At last it officially happens… Apple has announced that as of May 1st 2013, they will reject apps that are accessing the UDIDs. (Article from 9to5mac). After more than a year during which the industry thought they could get away by sneakily hashing UDID data, the UDID-doom-day has arrived. But why is the deprecation of UDID a good thing?

apple deprecates udid

Too Many Identifiers


The list of identifiers used by different networks and publishers is daunting…

  • UDID
  • IFA
  • Mac Address
  • IP Address
  • ODIN
  • OpenUDID

Add to this list hashed versions of these identifiers (SHA1, MD5) and the different ways to express and hash them (lower case, upper case, hexadecimal, etc.) and you are in trouble.

But why are advertisers and publishers using identifiers? Because Apple (unlike Google Play) does not provide a 3rd party way of tracking placements that converts, or in other words, let people optimise their non-iAd campaigns.

IFA is the official tracking method

This was true since the first release of the IFA (Identifier for Advertisers) – however it never really got the attention it deserved because people could still rely on UDID. As of March 2013, most of the traffic on the largest network does not support the IFA. If you were to only rely on IFA-enabled publishers the popular ad-exchanges you would be left with very little traffic. This situation in which the UDID was not officially banned forced a lot of people to use it because too few publishers made the switch. Now that Apple has taken the stance to officially reject the UDID, you can bet that you will see one of the fastest volte-face in the industry. Who is going to take the risk to lose all their revenue by sticking to the UDID?

Google SDK

Watch this page…  Admob SDK – as of March 28, 2013, the Admob SDK is still relying on UDID.


Google has been playing with the UDID for a while now. It’s high time they finally decide to play it by Apple’s rules and dump the UDID for good!

The Future

At long last, this will bring some simplification and homogeneity in the mobile tracking industry… It can only force the industry to adopt better standards and more accurate tools to track and optimise ad delivery. Next step, banning apps that are accessing and using MAC addresses for tracking purposes!

Posted in Mobile