By 2016 hundreds of companies were developing VR products.
Most of the headsets had dynamic binaural audio.
Haptic interfaces were underdeveloped. Haptic interfaces are systems that allow humans to interact with a computer using their touch and movements - like the Gloveone gloves that were being developed. This meant that handsets were typically button-operated.
HTC released its HTC VIVE SteamVR headset. This was the first commercial release of a headset with sensor-based tracking which allowed users to move freely in a space.