Why is my video or videosphere not playing on mobile in A-Frame VR?

Question

I have an A-Frame scene with a video or videosphere:

<a-scene>
  <a-assets>
    <video id="video" src="anothervideo.mp4></video>
  </a-assets>
  <a-video src="myvideo.mp4></a-video>
  <a-videosphere src="#video></a-videosphere>
</a-scene>

When I test in iOS or Android, I just see a black screen. It works on desktop.

Answer 1

Speaking of leveraging Enter VR button, try:

<a-scene>
<a-assets>
  <video id="video" src="anothervideo.mp4"></video>
</a-assets>
<a-video class="video" src="myvideo.mp4"></a-video>
<a-videosphere class="video" src="#video></a-videosphere>
</a-scene>

<script>
  function playVideo () {
    var els = document.querySelectorAll('.video')
    Array.prototype.slice.call(els).forEach(function(el) {
      el.components.material.material.map.image.play()
    })
  }

  document.querySelector('.a-enter-vr-button').addEventListener('click', playVideo)
</script>