Xibo android rendering working principle

Hello,

Is there any excerpt anywhere on the operating principle of the XfA application?

I think I noticed (due to a slight lag between contents of different nature) that Video, Images and HTML are not rendered the same way.

Is everything transformed to HTML and rendered inside a webview, or are they rendered by separate means?
What webview is used, is it embedded in the player app or does it use a system wide app?
If so, what are the best versions to use?

Thank you,
Nicolas