The experimental Web APIs introduced by Crosswalk, like Presentation<link>, Device Capabililties<link>, LaunchScreen <link> are supported in XWalkView.

For your reference:
Presentation: http://webscreens.github.io/presentation-api/
Device Cap: http://www.w3.org/2012/sysapps/device-capabilities/

@kurli, do you provide the link of LaunchScreen API documentation?