Google Tilt Brush has normalized drawing in 3D space, so the next obvious step is animating drawings in virtual reality.
While multiple people are working on tools to enable classical animation on vr platforms, the furthest along might be Animvr, developed by Milan Grajetzki’s Nvrmind. (The National Film Board of Canada has an advanced stereoscopic 3D tool for hand-drawn animation called SANDDE, but it is not commercially available.) Animvr, currently in development, allows users to draw and animate in vr by providing a set of tools based on traditional animation concepts like frames, onion skins, and timelines.
An alpha release of Animvr was made available to testers this week, and a publicly available release on SteamVR is expected in early 2017.