Great app, I really like the way it deals with nested comments. Just a couple suggestions:

* Maybe you could visually distinguish the "headline" item in any given view from the items under it? E.g. when you're looking at a story and its comments, they're all displayed like visually identical items in a single list. Maybe the story (or the top comment, if you're reading a thread) could be made to stand out somehow?

* An icon to jump directly to stories from the home page?

* You could register the app with an intent filter for urls under http://news.ycombinator.com/ (like e.g. Reddit Is Fun does for their app – see the app manifest in their GitHub repo for details)