This document discusses building HTML5 virtual reality apps using Intel XDK. It explains that HTML5 is compelling for cross-platform VR apps because it is cross-platform, collaborative, and allows editing and testing changes quickly. Intel XDK can be used to build HTML5 and Cordova apps, and Cordova APIs allow accessing device features through JavaScript. The document provides examples of how to implement stereoscopic rendering, head tracking, and accessing device features in HTML5 VR apps.