A-Frame is pioneering, making architectural choices which may or may not pan out. Think Angular 1.
Neither WebVR nor UnityVR are currently usable on Linux. Think "I got my simple test scene to not core dump!". MacOS has almost nothing. Android has some support from both, and iOS less, but I'm unfamiliar with them. There's a lot of Windows-centrism in the current VR community - if someone says something "works", they likely mean on Windows, with android a distant second. Once upon a time, Microsoft would write MS-only non-standard web extensions... now Google and Mozilla are doing the writing for them.
So, I generally recommend: Unity on Windows for VR beginners and exploration; Unity or https://www.unrealengine.com/ (better Linux support) for more serious work. But there are other options. And for WebVR, Windows (or Android?), A-Frame for beginners, direct three.js for more serious work, and perhaps aframe-react for exploratory VR webdev.
Aside: And for a hypothetical never-met person who wishes to run a Vive with WebVR on Linux, there's also my https://github.com/mncharity/node-webvr-alt-stack ... but I didn't finish WebVR 1.1 and A-Frame support.
A-Frame integrates with webdev tooling - eg https://github.com/aframevr/aframe-react . Think HTML5 vs Flash.
A-Frame is pioneering, making architectural choices which may or may not pan out. Think Angular 1.
Neither WebVR nor UnityVR are currently usable on Linux. Think "I got my simple test scene to not core dump!". MacOS has almost nothing. Android has some support from both, and iOS less, but I'm unfamiliar with them. There's a lot of Windows-centrism in the current VR community - if someone says something "works", they likely mean on Windows, with android a distant second. Once upon a time, Microsoft would write MS-only non-standard web extensions... now Google and Mozilla are doing the writing for them.
So, I generally recommend: Unity on Windows for VR beginners and exploration; Unity or https://www.unrealengine.com/ (better Linux support) for more serious work. But there are other options. And for WebVR, Windows (or Android?), A-Frame for beginners, direct three.js for more serious work, and perhaps aframe-react for exploratory VR webdev.
Aside: And for a hypothetical never-met person who wishes to run a Vive with WebVR on Linux, there's also my https://github.com/mncharity/node-webvr-alt-stack ... but I didn't finish WebVR 1.1 and A-Frame support.