Obtaining a UDID programmatically will not work with iOS7.0 and above, since Apple has obviously moved it to the "Private API" space for security reasons. However, you can still see the UDID of the device when it is connected to Xcode (Xcode-> Organizer-> {Your device name} โ Identifier). You can also see it when the device is connected to iTunes by clicking on โSerial Numberโ (it switches between the serial number and the UDID). You should ask your beta testers to find the device UDID this way and send you through, I suppose.
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