> It's hard to deep-link into an app.

Disagree. Case in point: steam://friends https://www.iana.org/assignments/uri-schemes/prov/steam

/s/ steam for news://home or news://business/26-05-2015-oil-prices

The content could (and definitely should) still be html, obviously not everybody you link to is going to want to install the news app and it should fall back to opening in a browser, but if you want to wrap a fancy interface around what should just be text there's your solution.