Google has released its YouTube VR app, previously available on Daydream, on SteamVR. The app allows users to browse YouTube videos through an interface in 3D, 360-degree space, and watch any of the innumerable 360-degree videos available on YouTube. It also allows for virtual big-screen viewing of standard format YouTube videos, in a setup similar to that found on, say, the Hulu app for PlayStation VR.
You can download it for free right now and try it out.
Unfortunately, the YouTube VR app doesn't seem to be working for many users, who have taken to the app's Steam community page, reviews, and discussion forums to complain about crashes and other problems. Users are posting their hardware specs as they report that it crashes on startup every time. Additionally, users have complained that it makes poor use of only one of the Vive's controllers, that quality is low, and that many SBS stereoscopic 3D videos are not working—which is obviously a huge omission