Also, definitely worth trying out this AR.js demo if you're running the beta: https://freinbichler.me/apps/web-ar/
Always thought it was a little peculiar that the Media Capture APIs are tied to what is otherwise a very data/protocol-oriented spec.
Wish we could have had a camera feed in a canvas element on Mobile Safari a few years ago without having to wait for the entirety of WebRTC to be vetted. :P
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And now, for my own unrelated Web API peeve:
Beyond service workers and all that jazz, I'm a little bummed out that the Pointer Events API isn't even listed on the Webkit Feature Status page: https://webkit.org/status/
It just seems like such a pleasant unification of all of the input-type APIs (mouse, touch, pen, hypothetical future peripherals...)
At least touch events have a "force" property with Apple Pencil input in the meantime. No tilt though.
Maybe next year :/