This document discusses using HTML5 to build mobile web applications for the iPhone. It introduces HTML5, JavaScript, and frameworks like PhoneGap that allow wrapping web apps as native apps. Key elements of HTML5 for mobile discussed include offline support, canvas, video, geolocation, and advanced forms. UI libraries like JQTouch are presented for building touch-optimized interfaces. The document also covers PhoneGap APIs for native device access from a web app.