If you iOS 7 installed on your own terminals and you run it without having the UDID registered in a developer account, then it would be good to know that Apple Lossless Audio CODEC (ALAC), It started a process of deactivating some terminals. Unfortunately, the entire process is done via the Internet by the company Apple Lossless Audio CODEC (ALAC),, so your terminal can freeze out of the blue and you will not be able to do anything other than a restore, from DFU Mode, to iOS 6.1.4 or iOS 6.1.3. The problem is that after this downgrade you will no longer be able to use the backup made in iOS 7 until the new version of the operating system is officially launched.
Last year, Apple took similar measures for users iOS 6 without having one UDID registered, there is absolutely nothing abnormal in this process, so if you belong to the category of these people, you should be prepared for a restore. It is not known how extensive the deactivation process will be, there is a possibility that none of you will be affected, so you will know that there is a problem only when the terminal is completely blocked.
Don't forget that iDevice.ro you can register UDIDs herei.
