// OnGUI
    void OnGUI()
    {
        // Show i-mobile & Unity logo
        manager.AddImobileLogo();
        manager.AddUnityLogo();

        // Create Ad Buttons
        // TODO: Refactor index. Not cool at all.
        var index = 0;

        if (manager.SelectedTabIndex == 0)
        {
            manager.SPAds.ForEach(ad => {
                string buttonSizeStr;
                if (ad.AdWidth.HasValue)
                {
                    buttonSizeStr = "(" + ad.AdWidth + " x " + ad.AdHeight + ")";
                }
                else
                {
                    buttonSizeStr = "(全画面)";
                }
                var buttonTitle = ad.DisplayName + " " + buttonSizeStr;
                if (manager.AddLoadAdSceneButton(index, buttonTitle))
                {
                    if (!ad.AdWidth.HasValue)
                    {
                        // SetScreenOrientation
                        Screen.autorotateToPortrait           = true;
                        Screen.autorotateToLandscapeLeft      = true;
                        Screen.autorotateToLandscapeRight     = true;
                        Screen.autorotateToPortraitUpsideDown = true;
                    }
                    Application.LoadLevel(ad.SceneName);
                }
                index++;
            });
        }
        else
        {
            manager.TabletAds.ForEach(ad => {
                var buttonSizeStr = "(" + ad.AdWidth + " x " + ad.AdHeight + ")";
                var buttonTitle   = ad.DisplayName + " " + buttonSizeStr;
                if (manager.AddLoadAdSceneButton(index, buttonTitle))
                {
                    manager.SelectedAdInfo = ad;
                    Application.LoadLevel(manager.TabletAdSceneName);
                }
                index++;
            });
        }

        // Create a Tab to switch SP <=> Tablet
        manager.AdTypeSelectTab();
    }