You can find all of our hardware documentation here including how to read GPIO values:
var tessel = require('tessel');
var port = tessel.port.A;
// We'll read the value of port a, gpio 1
var pin = port.digital;
// Set the pin as an input
// Read the state of the pin
var value = pin.read();
I haven't read any good websocket references. When I made my demo, I just looked at the examples shown in the README of the
nodejs-websocket library. Is there a specific issue you're running into with websockets?
In theory bootstrap should work, especially if it's not hosted on the device. ie, if in the HTML your web server serves to the client links to remote stylesheets and scripts so that they don't have to be held in Tessel's (relatively) small memory or transferred through our lower-power WiFi chip:
<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css">
<!-- Optional theme -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap-theme.min.css">
That being said, I haven't tried this so let me know how it works in practice!