Slidedeck used to give an introduction to WebXR. It also contains the slides for a short introduction to WebVR using A-Frame and Glitch.me by showing the HTML and JavaScript.
7. Cardboard DayDream Oculus ViveGearVR Windows MR
Chrome Android
Samsung Internet
Chrome Android
Oculus Browser
Samsung Internet
Chrome
FireFox
Opera
Supermedium
Chrome
FireFox
Servo
Opera
Edge
Where is WebVR?