PC Magazine: “Stanza is the best e-book reader for the iPhone, and my favorite.”
21 Cool iPhone Apps - Stanza

What sort of content can I read with Stanza?

Anything! However, Stanza is especially designed for reading large bodies of text where formatting is not an integral part of the reading experience. It is more appropriate for reading novels, stories, essays, and news articles. Graphics-heavy content like textbooks and multimedia web sites will be difficult to read using Stanza.