Some iOS app developers have reported that Apple has begun rejecting apps that access a device’s unique identifier (UIDID), a move that was initially brought up when Apple disapproved the UDID in iOS 5 back in August of last year.

It now appears that the it is officially taking into effect at a time of heightened scrutiny over the company’s privacy safeguards. UDIDs are used by some app developers to track user behavior, but their use has been under scrutiny since they are permanent and users are not able to block the sending of their UDIDs to third parties.

TechCrunch has reported that two of Apple’s review teams have begun ‘blanket rejections of apps that use UDIDs’ this week, and that the week after, four teams will issue rejections, until all ten of their review teams reject apps that use UDIDs.

Since this move away from UDID access has been in the works for a considerable amount of time, iPhone and iPad users don’t need to really panic about all their favorite apps being taken off the App Store. However, developers that still use UDIDs may now really need to work to find an alternative.