We want to make it even easier to use device APIs. Device Proximity has a sister spec called User Proximity that allows you to be notified when the user is “near” or “far”. So, instead of looking at sensor values and determining where the user is, you can simple register for a callback:
window.addEventListener("userproximity", callback, true);
function callback(a) {
// d=
if (a.near)
d.innerHTML = "User is near"
else
d.innerHTML = "User is far"
}
This work is being tracked in Bug 751663 and should be landed soon.
