HN is a really lightweight webpage, which looks good even on mobile browsers. The app navigation is similiar to the browser nav and even commenting is similiar as within browser. so why spend $3 to have a bookmark of HN?
EDIT: It was created by HN's own ronnier. http://news.ycombinator.com/user?id=ronnier
On iPhone: font sizes are really too small, voting arrows are practically not hittable without zooming in and trying to zoom in on the articles list confuses Safari (probably because of all the nested tables)
yes, its a personal feling. but i think one time zooming is ok and not worth buying an app.