This is a simple calculator app. I used angularjs to write it, also scripts/web-server.js is the one from http://docs.angularjs.org/tutorial (Great tutorial). To start it you need to go in the calculator folder and start the web-server with ./scripts/web-server.js After that go to localhost:8000/app/index.html and for example write 1+{3+8*(3+2)-3*[4*(2+3)+2*(6-1)]}*4 in the text field. Press the link and it should output the result of the expression.