It has just come to light that the UIDevice uniqueIdentifier property is deprecated in iOS 5 and unavailable in iOS 7 and above. No alternative method or pr
Apple has added a new framework in iOS 11 called DeviceCheck which will help you to get the unique identifier very easily.
Read this form more information.
https://medium.com/@santoshbotre01/unique-identifier-for-the-ios-devices-590bb778290d