Isn't it all about the URL?

The URL bar provides a huge advantage for web applications over native ones. It allows us to reference states, bookmark them, and share them with our friends. In a well-behaved web application, any application state transition results in a URL change, and any URL change results in a state transition. In other words, a URL is nothing but a serialized router state. The Angular router takes care of managing the URL to make sure that it is always in-sync with the router state.