The advertising identifier does not change on every call. Using "CFUUIDCreate" IS WRONG, though. It generates a GUID. That's what CFUUIDCreate is supposed to d

The advertising identifier does not change on every call. Using "CFUUIDCreate" IS WRONG, though. It generates a GUID. That's what CFUUIDCreate is supposed to do. But it's the wrong method to call to get the advertising identifier. You get the advertising identifier from ASIdentifierManager, and it does not change unless the user resets it.