Chris McCann of Greylock Partners posted a great primer on the VR market ecosystem (circa July 2015) on Medium.com, covering VR devices & controllers, VR cameras, developer tools, content, platforms and applications.
The body of Chris’ post includes more companies than are featured in the graphic above. As Chris notes, his list is biased towards startups and companies that have raised funding. The list is also biased towards the West, and therefore does not cover the burgeoning VR market in China and Asia.
Sure to have evolved by the time you read this.