HOOV is a wireless sensing method that complements existing virtual and augmented reality headsets to support hand tracking outside the field of view of the headset's cameras. In this example app of our system, a participant is building a structure composed of blocks with different sizes. When the user places an object onto the structure, his hand is tracked by the headset's cameras (left). As the user reaches for a block just to his right (right), his hand leaves the field of view of the cameras. Now, HOOV continuously estimates the 6D position and orientation of the wrist using the 6-axis inertial measuring unit attached to the wrist during the time the hand stays outside the field of view.