Kindle Reader for iPhone: Excellent
Amazon Kindle App for iPhone is excellent. The Reader lets you view in landscape or portrait mode, zoom-in/zoom-out for readability. One thing: to *delete a Kindle book from your bookshelf*, you press down and hold the Kindle book you want to delete, then eventually the Kindle App will ask you what you want to do with your selection -- there is no drop-down command selection, so that action was not obvious to me, and required a tech support call -- saving you all the trouble by this note.
Bill-from-SF about
Kindle – Read Books, eBooks, Magazines, Newspapers & Textbooks, v5.13.1