What about sensors/stuff on the hardware that the browser may not be able to access?
Edit: I have seen some browser demos that could show your phone's orientation. In the past the camera trigger was not reliable that was in 2013-2014 if I recall dang time flies.
Edit: I have seen some browser demos that could show your phone's orientation. In the past the camera trigger was not reliable that was in 2013-2014 if I recall dang time flies.