Hello Matteo
It doesn't answer your question, but we've used Freeboard hosted by Node Express for a dashboard.
You can use them to host your dashboard or host it yourself.
It is super easy to set up - we used a websocket in Node-RED to pass the data as Nick outlined.
There was a gist posted on this list a while ago that showed howto setup a websocket input for Freeboard. We also customised it to give us another larger text widget - the widgets are quite well constructed and easy to extend.
Kind regards