HTML5 compatibility on mobile and tablet browsers

That's exactly what I came here to say.

Android 'supports' CSS transforms, but a bug in Android 2.2+ (works fine in 1.9) means that you can't apply more than one simultaneous transition to a single element at a time (I don't know if this has been fixed in more recent versions, but it's still a big backwards compatibility issue).

iOS MobileSafari supports 'multimedia' (and is listed as such), but it's not until iOS 6 lands that we're getting proper Web Audio API support to actually provide a non-hacky way of playing sound for uses like games that require precise timing.

A binary yes/no really doesn't encapsulate the subtlety and complexity of mobile feature support.

I agree - lists like these don't really have value if you're doing serious mobile web development. A few more examples of broken and inconsistent implementations:

• Viewport - this meta tag isn't supported on HTC phones, so your slick CSS media queries will expose a terrible UI in some cases.

• Websockets - the specification was changed after vendors implemented it, so you have to support multiple authentication schemes on the server side.

• Video - every vendor has their own take on how the controls should look, and certain vendors (I'm looking at you, iOS) disable or override the w3c default specification, so you have to sniff user agents to make a decent custom control. That's not to mention the difficulty of supporting all the various formats.

What adds to the pain is that the browser vendors don't always do a great job of keeping their APIs current, so you have to play the trial-and-error game to tease out the reasons you're having trouble - a game that is exceptionally difficult when the problem only occurs on the mobile device itself.

I would like to work on this project if I could retire. Either that or Inkscape.