title: Get serial number of device on iOS 8
body: <p>For an in-house application, we were using the following code <a href="https://gist.github.com/0xced/566994">UIDevice+serialNumber</a> 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?</p>