Support the HTML Media Capture API
Full support for the HTML Media Capture specification (W3C Candidate Recommendation 2014). This would allow simple access to the native video camera using '<input type="file" name="video" accept="video/*" capture>' on Windows Phone.
(see "example 2" in spec)
At the moment, the only way to do this is to create your own camera using the navigator.getUserMedia implementation, which is more complex and can differ per platform (UI and logic). The simpler input capture type already works on iOS, Android, and Blackberry providing a fully-functional native camera with requisite platform-specific look and feel.
PS The HTML Media Capture API should not be mixed up with the already implemented Media Capture and Streams API (https://www.w3.org/TR/mediacapture-streams/)