Window: deviceorientation event

if (window.DeviceOrientationEvent) {
    window.addEventListener("deviceorientation", function(event) {
        // alpha: rotation around z-axis
        var rotateDegrees = event.alpha;
        // gamma: left to right
        var leftToRight = event.gamma;
        // beta: front back motion
        var frontToBack = event.beta;

        handleOrientationEvent(frontToBack, leftToRight, rotateDegrees);
    }, true);
}

var handleOrientationEvent = function(frontToBack, leftToRight, rotateDegrees) {
    // do something amazing
};