Update index.md

Author: torum

docs/index.md

@@ -42,11 +42,12 @@ MPDCtrl for desktop -
 ![MPDCtrl](https://github.com/torum/MPDCtrl/blob/master/images/screenshots/v3/Debug.png?raw=true) 
 
 
-### MPDCtrl for mobile
-sometime in the future...
+## MPDCtrlX for cross-platoform
 
-![MPDCtrl](https://github.com/torum/MPDCtrl/blob/master/images/screenshots/mobile/iOS-v0.0.0.1-screnshot.png?raw=true) 
+[MPDCtrlX](https://github.com/torum/MPDCtrlX) is a cross-platform desktop GUI client app based on [Avalonia UI](https://avaloniaui.net/), a port of WPF-based [MPDCtrl](https://github.com/torum/MPDCtrl).  
 
+Currently under developement.
 
+![Screenshot](https://github.com/torum/MPDCtrlX/blob/main/Docs/Images/MPDCtrlX-Screenshot-1.png?raw=true)