             return false
         }
 
-        let systemVersion = UIDevice.current().systemVersion
+        let systemVersion = UIDevice.current.systemVersion
 
         if systemVersion.compare(requiredOSVersion, options: .numeric) == .orderedDescending ||
             systemVersion.compare(requiredOSVersion, options: .numeric) == .orderedSame {

        Current installed version of your app
     */
    private var currentInstalledVersion: String? = {
        return Bundle.main.objectForInfoDictionaryKey("CFBundleShortVersionString") as? String
    }()

    /**

private extension UIAlertController {

    func show() {
        let window = UIWindow(frame: UIScreen.main.bounds)
        window.rootViewController = UIViewController()
        window.windowLevel = UIWindowLevelAlert + 1
        
