Thought I would let he community know that there is a new GMAT prep application for the iPhone. Its called "TestPundit iGMAT". I found it while scrolling through the "Education" category on my iPhone App Store.
I like the content (good questions and review topics). The UI can be a bit better but overall pretty good. Just posting for the benefit of other GMAT takers who need on-the-go gmat prep like I do :)