The purpose is to support playing flv without requiring client side script like actionscript.
Anyone knows?
HTML5 video support is lacking at best currently. Many browser vendors each use different codecs (Safari/MS use H.264, Firefox Opera use Ogg/Theora). None of the browsers support the .FLV format to display video. .FLV and .F4V are the Flash Player's format. HTML5's primary intention is to reduce the need for plugins, so Flash Video is not part of the spec. To answer your question though: it depends on the mobile browser's implementation of the HTML5 specification and their selection of codec.