There is an equivalent for identifierForVendor in watchOS that can be used to generate a unique ID. if let uuid = WKInterfaceDevice.current().identifierForVendor?.uuidString { print("UUID is",uuid) }

Now there is an equivalent for identifierForVendor in watchOS. if let uuid = WKInterfaceDevice.current().identifierForVendor?.uuidString { print("UUID is",uuid) } This can be used to generate a unique ID.