A simple canvas app using SocketIO.
First step - Go to the terminal and do 'npm install' to install all the dependencies.
Second step - Launch the server by 'node app.js'
Third Step - Go to the URL http://localhost:4000/{yourRoom}
{yourRoom} - Indicates any string which will be used to create your private room.
Any one joining this room will be able to see what you are drawing.