Exercise : study the code of this smart watch https://github.com/Utopiah/webVR-PebbleTime-interface/blob/master/src/app.js . How does it connect to a virtual world? Based on your previous exercise using Firebase, how can you integrate the two?
See also a workshop organized in early August on the topic http://vrlab-brussels.info/wiki/Internal/DIYElectronicWorkshopPreparation