Sort of. A Chrome App can only have a single HTML page in a window (navigation is not allowed). But you could allow pseudo-navigation within the app by either:
a) having JavaScript tear down the page contents and build a new DOM structure within the same document, so it looks like a brand new page,
b) having a WebContents within the page that contains HTML. WebContents is allowed to navigate, but it isn't allowed to use Chrome App APIs (it's effectively a web browser inside your app).
Clicking links and having them open in a new tab works as you would expect (just set target="_blank").