Has any progress been made so far (if so, can we get a sneak peak)? I was wondering why you’d want to do this in nodejs/express since the functionality you described can be achieved with ‘simple’ HTML/JavaScript. This spares you of having to go through the node/express stuff, and keeps it relatively simple. Also, why would you limit the functionality to one device only? - Questions are out of interest, not criticism 
There have been things like this made before, this one for example: (which is really helpful!)
I tried to partially recreate this in order to try out the SparkJS library, and (so far) ended up with this page.