Google Cardboard JavaScript viewer
iOS 13 limits use of the accelerator to secure websites, meaning that it is necessary to run the local development server over HTTPS. This can be done as follows:
pipenv install
pipenv run python3 service.py
<div
data-src="603822945.523954.jpeg"
data-projection="equirectangular">
</div>
...
<script type="module">
import { Cardboard } from './cardboard.js';
Cardboard.initialize( document.body );
</script>