AppDelegate.swift

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        
        self.registerForAppTrackingTransparency(launchOptions)
        return true
    }

    
    private func registerForAppTrackingTransparency(_ launchOptions: [UIApplication.LaunchOptionsKey: Any]?) {
        if #available(iOS 14, *) {
            ATTrackingManager.requestTrackingAuthorization { (status) in
                if status != .notDetermined && status != .restricted {
                    if status == .authorized {
                        print("authorised")
                    } else if status == .denied {
                        print("denied")
                    }
                }
            }
        } else {
            /// fallback
        }
    }