Get serial number of device on iOS 8
For an in-house application, we were using the following code UIDevice+serialNumber to get the device serial number. However, it seems that with iOS 8, the registry key "IOPlatformSerialNumber" is empty. Can the serial number be obtained any other way?
Answer
Answer: No.
There are currently floating solutions around abusing the .mobileconfig, but they add other problems due their nature.
UUID was removed for a reason. See the news around privacy and the summon of Apple by the US Senat from 2011 to gain an understanding why this had to be changed. http://arstechnica.com/apple/2011/04/apple-google-asked-to-join-judiciary-hearing-on-mobile-device-privacy/
Abusing the underlying march port to get the device serial number as replacement of the UUID is not the solution. Same now for abusing the mobile config and guess how long that will work.
You have plenty of decent ways to handle any situation where you used device identification before. Especial in an enterprise environment where you have cryptography and MDM is absolutely no point to track a device like this.