How Apple’s UDID Deprecation Affects You

March 27th, 2012 § 0 comments § permalink

Last August, the iOS developer community discovered a small change with potentially large implications that came with the introduction of iOS 5.0: the deprecation of the UDID. The UDID is a highly used unique identifier for each iOS device; somewhat like a social security number for your phone or tablet.

UDIDs are widely used in the context of creating and distributing ad-hoc, beta builds. However, there have been a number of security and privacy concerns raised when it was found that this identifier was being used for many other purposes.

To address these concerns Apple has given a new alternative, the UUID, and as of late has been urging more and more developers to expedite the replacement of the UDID in their apps. Some reports indicate that Apple is starting to actually reject apps that reference UDIDs.

From the iOS 5.0 release notes:

Deprecated in iOS 5.0


An alphanumeric string unique to each device based on various hardware details. (read-only) (Deprecated in iOS 5.0. Instead, create a unique identifier specific to your app.)
@property (nonatomic, readonly, retain) NSString *uniqueIdentifier
Special Considerations

Do not use the uniqueIdentifier property. To create a unique identifier specific to your app, you can call the CFUUIDCreate function to create a UUID, and write it to the defaults database using the NSUserDefaults class.

When making this change, it is important to note the differences between the UDID and the new UUID. The UDID was a unique identifier for your phone that was the same across all applications. It remained constant even when you deleted and reinstalled an application, allowing for the application to still know who you are. Now, with the UUID created through CFUUIDCreate, it is only unique for an app, and on one particular install. Once you delete and reinstall the app, a new identifier is created. If you do need the new UUID to last beyond app deletion and reinstall, the value could be stored in iOS’s keychain instead.

If you would like to know more about the implications that this will have on your app, do not hesitate to contact us for more information.

Cross-posted from the Xtreme Labs blog.

App Review: Tiny Tower

October 1st, 2011 § 0 comments § permalink

Tiny Tower
62479 Ratings
Company: NimbleBit LLC
Platforms: iOS, iPhone and iPad

Tiny Tower is an addictive time waster app that brings back memories of the Tamigotchi toys, paired with the addictive element of Farmville. In this app, you act as a landlord of a tower where you build new floors with residential units or stores. You want to keep your tenants happy, and help them work up to their dream job. It’s a perfect mix of the Sims and Sim City, but vastly simplified to be mobile friendly.

The notifications and urgency bring you back to the app multiple times throughout the day. Regardless if you close the app, your tower keeps building and you keep earning money. However, your stores also run out of stock and your tenants get angry, resulting in the constant need to babysit it. Great for the app, not so great for the day job.

I initially downloaded this app because it’s one of the best for in-app purchases, and I immediately see why. This app capitalizes on impatience, people not wanting to wait to build up their tower, and their price points are affordable with 0.99, 4.99 and 29.99 to purchase “Bit Bux”. Although I think 29.99 is a bit steep (I wouldn’t have hesitated on 19.99), the others provide a sense of instant gratification, and a shopping spree within the app.

A cute feature is “Bit Book”, which gives you a view of your tenants’ “Bit Book” status updates. It’s for pure entertainment value, and I find myself checking it just to see the hilarious updates (ie. “What is the trampoline policy in this building?”).

Things they do well: It keeps things simple, and is a great execution on a not so original idea. It’s extremely easy to navigate, and the purchase experience is speedy and seamless. It’s fully integrate with Game Center so you can see how your friends are doing and adds a competitive element. They also do a perfect transfer of your game across devices. A lot of games handle that poorly (Angry Birds, for one), in that you need to start from scratch per device.

Things they could do better: I need the ability to actually fully close out this app and stop it from running. I understand that they made it continue running in the background regardless so you could earn money, but it leaves me feeling uneasy with a slight sense of anxiety (or maybe I’m just neurotic). The pace could be sped up ever so slightly, but I understand that the pace is optimized to encourage in-app purchases. Also, the music? Snoozefest.