Hi Lars,

I don't see why not, you'll just need to be aware of which html 5 features are supported in the mobile browsers, but whatever is supported you can use.

Best,

Joe

The layout.master is already using the Html 5 doctype so yes you can use it anywhere subject to browser support since Html 5 is not yet a standard but is supported to greater or lesser degrees in browsers.

Note however that Windows Phone 7 currently has mobile IE 7 which probably won't support much, the next update code named mango will ship with mobile IE 9 or 10 I think so it will be much better.

Also note that even if different browsers support the audio/video elements the kind of files you can use (ie supported codecs) may still vary substantially.

Best,

Joe