You don’t add Default Folder or FontExplorer X Pro to your iPhone, you don’t choose your iPhone’s browser, and you don’t install plug-ins in your iPhone’s browser. This lack of extensibility may not please the Slashdot crowd but it’s the future of computing and browsing. The bulk of humanity doesn’t want a computing experience it can tinker with; it wants a computing experience that works.
HTML5, with its built-in support for video and audio, plays perfectly into this new model of computing and browsing; small wonder that Google and Apple’s browsers support these HTML5 features.