private void Awake()
 {
     if (instance != null && instance != this)
     {
         Destroy(this.gameObject);
     }
     else
     {
         instance = this;
         // DontDestroyOnLoad(this.gameObject);
         int height = (int)(Screen.currentResolution.height * resolutionPercentage) / 100;
         int width  = (int)(Screen.currentResolution.width * resolutionPercentage) / 100;
         //print(width);
         //print(height);
         Screen.SetResolution(width, height, true);
         DontDestroyOnLoad(this.gameObject);
     }
 }
    [Range(30,100)]
    public int resolutionPercentage=75;

    private void Start()
    {
        if (!FB.IsInitialized)
        {
            // Initialize the Facebook SDK
            FB.Init(InitCallback);
        }

        if (instance != null && instance != this)
        {
            Destroy(this.gameObject);
            return;
        }
        else
        {
            instance = this;
            SetResolution();
            GameAnalytics.Initialize();
            DontDestroyOnLoad(this.gameObject);
        }
    }