can I create a VR game in browser for multiple platforms (pc, iOS, Android?)

Good morning people of the mighty internet!

I want to create an vr app for multiple platforms (pc, android and ios) and it should be available to all of them via a webbrowser.
So would it be possible to create a html5 project, bring it online and all devices could use this to play the game? Like a browsergame for multiple platforms.

Would this work, or do I have to publish the game in the appstores to be able to play them on the smartphones?

I hope somebody can help me to solve this question (I am not that into the capabilities of the Unreal Engine)