Apple Begins Rejecting Apps for Using the Unique Device Identifier (UDID)

ios5 iconTechCrunch reports that Apple has begun rejecting iOS apps for the use of a unique device identifier known as the UDID. The site notes that several developers have reported rejections for the use of the UDID in the past week, and Apple is said to be ramping up the enforcement of this policy over the next few weeks.

As the name suggests, the UDID is a unique identifier for every iOS device. It's tied specifically to the hardware and can't be changed by the user. Apple had previously warned developers with the introduction of iOS 5 that the use of the UDID was deprecated and would be phased out. The sudden rejections, however, have caught some developers off guard:

“Everyone’s scrambling to get something into place,” said Victor Rubba, chief executive of Fluik, a Canadian developer that makes games like Office Jerk and Plumber Crack. “We’re trying to be proactive and we’ve already moved to an alternative scheme.” Rubba said he isn’t sending any updates until he sees how the situation shakes out in the next few days.

The reason for the phasing out of UDIDs from developer use is due to increased pressure on Apple due to the privacy implications. Apple and several App developers have been sued over the use of the UDID to track users across different apps. While the UDID doesn't specifically identify a user, the sharing of UDIDs across ad networks and apps can help piece together a valuable picture of activity and interests of the user of a specific device. Apple seems to be requiring apps to generate their own unique identifiers for each installation to avoid this ability to share such information across apps.

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Top Rated Comments

Virtualball Avatar
173 months ago
Why are developers "scrambling" for a solution to this? They've known for how many months exactly that this was coming?

:rolleyes:
Score: 37 Votes (Like | Disagree)
dejo Avatar
173 months ago
"We're trying to be proactive..."

Really? iOS 5 and Apple's warning have been out there for quite a while now. Seems at lot more reactive to me.
Score: 36 Votes (Like | Disagree)
axonic labs Avatar
173 months ago
How is using UDID a good idea for storing high scores, preferences etc? What happens when users upgrade to a new device?

yep, there are non ad uses for it.

The tough part is that if Apple doesn't allow a well defined transition period for it (where devs can still use the udid), users' apps that do use it for something like above (connecting a device to high scores, storage of preferences / data) will have their data lost on the next app update.

arn
Score: 26 Votes (Like | Disagree)
axonic labs Avatar
173 months ago
How are developers "caught by surprise" and are "scrambling" as it is not exactly news. It sounds like apps are being rejected during the app review process so existing apps should be okay. The article makes it a bigger deal than it actually is.
Score: 25 Votes (Like | Disagree)
axonic labs Avatar
173 months ago
It's just not a good idea to use UDID for storing high score and other preference data. The high score and preference really belong to the user and not the device (users can have multiple or change devices) and the app should use a "user id" rather than a "device id".

If the app has proper customer service, they can do a simple score-transfer. The user would have to prove that they upgraded their device by either logging into their old or new device with their username. If the old device broke, it becomes a little harder to prove the identity of players, but IPs can also prove useful.
Score: 20 Votes (Like | Disagree)
Pakaku Avatar
173 months ago
give me a better way that doesn't require registration.

arn
As I understand it, the problem with using the UDID is that it doesn't track your scores across devices. If you upgrade to a new iPhone, say goodbye to your highscores.

A better idea could be to just do it through Game Center, or being able to sync highscores to iCloud. You have to sign up if you want to use it for other things, anyways.
Score: 18 Votes (Like | Disagree)