Random question for you: In your single-page app, do you support bookmarking "locations" that take multiple clicks to get to, so rather than redo those clicks at a later date, the user can get there via the bookmark? (Assuming your site has locations that require multiple clicks to get to of course.)
Users of software don’t care for the terms developers use to label their creations, “web app” or “web page” — it’s all the same to them. More importantly, they expect an identical behaviour from both. So when a web app can’t recreate its state from URL it’s breaking a fundamental web UI convention.
Another core UI convention that is often disregarded by web app developers is link click behaviour, i.e. you expect anything that performs a function of a link to behave as it normally would when you click on it with mouse’s middle button, or right click → context menu, or left click with modifier keys (cmd/ctrl, shift). Everyone got used to this and when the pattern is broken it is most annoying.
it would be something like this:
http://example.com/#!/users/1234
Personally, I have found that for SPAs with centralized state, you can serialize the entire application state into the URL fragment. This means that no matter where the user is in the application, they can bookmark that URL and it would return them to exactly the same place that they were (authentication aside). The disadvantage is that the fragment doesn't necessarily "make sense" to the user, and the URL is too long to be conveniently remembered or retyped manually.
That said, it really was an offline app. We could've done it as a native Qt or .NET app. Even so, the standard AngularJS document fragment paths supported bookmarking and so on.