Single Page Applications (SPAs) are HTML applications driven almost entirely by JavaScript executing in the browser. We will consider why you might want to do that (hint: data-intensive mobile apps) and then look at a few apps that are built in this style. I'll show you some of the libraries and techniques I'm using and introduce you to one in particular, BreezeJS, an open source library for querying, tracking, validating and saving data in a JavaScript client.