In that case, I'd still have to either audit the app's code or trust the author. With mobile Web, I know it won't spy on me like that because the browser won't let it.
+1. RedReader[1] is just awesome. In fact it's one of the few UIs I've used that I felt completely at home with from the first time I used it. It's filled to the brim with tools and options but I always find what I'm looking for.