External Data? Sure; data doesn’t have to be local. Like, some applications are multi-targeted. They allow users to log in on their phone, desktop, tablet, Xbox, work PC, and even fringe technologies like Droid, IPhone, and IPad.
These apps probably persist user info and system data in central stores. And in most cases, they are probably exposed through web services. Let’s take a break from the hard work of UI design and consider the easy task of data access.