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

[MacRumors]

TechCrunch 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.

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

[Exotic-Car Man]

Sweet, thanks for posting my submitted topic!

For many developers, this is a very scary thing. For instance, this goes beyond just advertisers. For online games, UDIDs are used to identify specific users, to ensure that they don't get mixed up and that scores (if the game has scores) are being recorded properly. I know a couple apps that use UDIDs for this purpose.

[dejo]

"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.

[arn]

Originally Posted by Exotic-Car Man

Sweet, thanks for posting my submitted topic!

For many developers, this is a very scary thing. For instance, this goes beyond just advertisers. For online games, UDIDs are used to identify specific users, to ensure that they don't get mixed up and that scores (if the game has scores) are being recorded properly. I know a couple apps that use UDIDs for this purpose.

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

[Virtualball]

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

[axonic labs]

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.

[MattJessop]

I can see why this is going to cause a bit of a problem for developers so I sympathise a fair bit, but I think ultimately Apple is right to do this - I'd rather that Apple keep strict control over such privacy matters especially as the mobile platform grows massively as it has done - it's such things like this that make me less likely to use Android as a platform as it's harder for me to keep track of my own data. It doesn't mean that iOS is necessarily a better platform for privacy, but it certainly feels that I can keep track of what I own better.

[arn]

Originally Posted by axonic labs

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.

It's the sudden nature of it that might be an issue for some.

If you haven't already migrated your existing users' data off UDID, then you can't anymore.

arn

[axonic labs]

How is using UDID a good idea for storing high scores, preferences etc? What happens when users upgrade to a new device?

Originally Posted by arn

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

[Exotic-Car Man]

Originally Posted by axonic labs

How is using UDID a good idea for storing high scores, preferences etc? What happens when users upgrade to a new device?

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.


The whole scenario of Apple restricting apps' access to systems and developers "scrambling" to find a solution reminds me of another recent story.

[arn]

Originally Posted by axonic labs

How is using UDID a good idea for storing high scores, preferences etc? What happens when users upgrade to a new device?

simplest case is high score.

So you have a game, you want people to be able to save their high scores to the global leaderboard without having to register an account.

How do you associate the high scores on the leaderboard with their device/install without any sort of registration process? UDID (or equivalent) is one easy way.

arn

[axonic labs]

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".

Originally Posted by Exotic-Car Man

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.

[arn]

Originally Posted by axonic labs

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".

that requires registration.

pick a username, a password etc...

arn

[axonic labs]

It is an easy way but it's not a good way nor the right way (my opinion of course).

Originally Posted by arn

simplest case is high score.

So you have a game, you want people to be able to save their high scores to the global leaderboard without having to register an account.

How do you associate the high scores on the leaderboard with their device/install without any sort of registration process? UDID (or equivalent) is one easy way.

arn

[arn]

Originally Posted by axonic labs

It is an easy way but it's not a good way nor the right way (my opinion of course).

give me a better way that doesn't require registration. (or udid equivalent)

arn

[Pakaku]

Originally Posted by arn

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.

[axonic labs]

yes it does, but this is the problem to be solved and not the excuse. registration/username is not preferred because people don't like to sign up etc and there could be ways to solve this. One way would be to go without username for a while (using UDID or some device id) and then prompt the user to register and describe the benefits of registration (keep data across multiple devices and won't lose data upon device upgrade).

Anyways, I make apps and I prefer to do things right rather than quick. The downside is that making apps that way often takes much longer.

Originally Posted by arn

that requires registration.

pick a username, a password etc...

arn

[arn]

Originally Posted by Pakaku

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.

sure, it's not the only solution you'd have available. If you care about your score, you register an account. But no game dev is going to require registration just to post high scores.

arn

[DESNOS]

Originally Posted by arn

give me a better way that doesn't require registration.

arn

I think this is why Game Center has seen such popularity. No registration is needed assuming you already registered an Apple ID. Registration may not be the easiest method, but it clearly is the best in terms of flexibility, especially when the login is device-wide.

[arn]

Originally Posted by axonic labs

One way would be to go without username for a while (using UDID or some device id) and then prompt the user to register and describe the benefits of registration (keep data across multiple devices and won't lose data upon device upgrade).

Of course, but we're not building an app here.

You just asked for why you would use UDID, and I gave you probably one of the biggest reasons. I'm not saying you would use it exclusively. Of course, you'd offer user registration too. Though the vast majority of your users would likely never register.

But, my point is. If you built a game using that technique (anonymous UDID high scores), all your unregistered users will lose their high scores on their next update.

arn

----------

Originally Posted by DESNOS

I think this is why Game Center has seen such popularity. No registration is needed assuming you already registered an Apple ID. Registration may not be the easiest method, but it clearly is the best in terms of flexibility, especially when the login is device-wide.

Again, obviously Game Center exists now. we're just talking about how someone might have used the udid.

arn

[iEvolution]

Is there no way for developers to associate scores based on iTunes account name instead?

UDID should not have been allowed to used in the first place, cudos to Apple for giving users a little more privacy, lord knows everyone else is trying to eliminate privacy, especially the government.

[axonic labs]

The developers who chose to use the UDID are making apps and I think it's the wrong thing to do in the first place because it won't survive device change/upgrade. People would already lose their high scores when they upgrade their device and now they would lose their high scores when they update the app on the same device as well.

I am not trying to be argumentative here. Just trying to illustrate that these problems could have been avoided with a little more thought on the developers side.

Originally Posted by arn

Of course, but we're not building an app here.

You just asked for why you would use UDID, and I gave you probably one of the biggest reasons. I'm not saying you would use it exclusively. Of course, you'd offer user registration too.

But, my point is. If you built a game using that technique (anonymous UDID high scores), all your unregistered users will lose their high scores on their next update.

arn

[DESNOS]

Originally Posted by arn

Again, obviously Game Center exists now. we're just talking about how someone might use the udid.

arn

You can store settings on an per-install basis, that is, the settings will be there until the user manually deletes the app. Even updates can't mess with these settings. It isn't as great as "per device" settings, but "per install" is how most apps work anyway, and gets the job done in my opinion. I can supply the code to do this if needed.

[Lokheed]

iOS 5 was released to developers on June 6th, 2011. Apple announced the deprecation of UDIDs on August 18th, 2011 and this is there wording: "Deprecated in iOS 5.0. Instead, create a unique identifier specific to your app." That's 8 months ago. These are facts.

Looks like Apple not only gave enough advanced notice, but also told developers exactly what to do to workaround the problem.

Another article that only serves to exemplify the laziness, self-righteousness, and extreme sense of entitlement of some people.

[arn]

Originally Posted by axonic labs

I am not trying to be argumentative here. Just trying to illustrate that these problems could have been avoided with a little more thought on the developers side.

But you yourself offered UDID usage as part of your solution (above). And it was also an Apple sanctioned technique prior to iOS 5. I'm certain if you had needed a similar system pre-iOS 5, you would have used the UDID and not thought twice about it.

arn

----------

Originally Posted by DESNOS

You can store settings on an per-install basis, that is, the settings will be there until the user manually deletes the app. Even updates can't mess with these settings.

wouldn't work for global high scores.

Edit: for the record, I'm not "pro-UDID" or anything. Just offering some counter discussion.
arn