Is anyone aware of a method to get the user's App Store nickname? I know about the CloudKit method fetchUserRecordIDWithCompletionHandler, but this returns the user first and last name, not the nickname that the user uses to e.g. write reviews on iTunes. Thanks
Using fetchUserRecordIDWithCompletionHandler and discoverUserInfoWithUserRecordID is the only way to get information about the current iCloud user.
Besides that you do have to be aware that starting from iOS 9 you wont't get the first and last name anymore only a displayname. For more info see https://developer.apple.com/library/prerelease/ios/documentation/CloudKit/Reference/CKDiscoveredUserInfo_class/index.html#//apple_ref/swift/cl/c:objc(cs)CKDiscoveredUserInfo