A discussion of VR locomotion wouldn't be complete without discussing VR controllers at least a little bit. What you've got in your hands, under your feet, holding you up, or letting you roll around in obviously makes a huge difference.
We are discussing WebVR, which, while very easy for people to get into, probably means that your users may not have all of the various types of VR gear handy. If you do have gear handy, you may still find that for your app, simpler types of locomotion are better, and they are certainly faster to code.
When discussing equipment, people discuss Degrees of Freedom (DOF). This really is less about strictly considering degrees of freedom but mostly about what is tracked.
If you have a handheld ...
