"HTML5 Enhancements
Tap in to new capabilities for your apps and sites webOS 2.0 adds a number of new HTML5 features and enhancements, giving you more tools to work with when building apps and sites for webOS. Highlights include: Enhanced Canvas support, including image data and gradients
Support for Web Storage—both local and session storage
Geolocation support, allowing websites to access location information with the user’s permission
Application Cache, which lets websites cache resources on the device for offline use"

Intro to webOS 2.0 - Palm Developer Center