You can search the New American Bible (which includes the apocrypha) by selecting an individual chapter from the old or new testament. Searching for a specific word or phrase is not too easy as you have to search via the main website (rather than the specific iPhone website). One problem highlighted by the This Lamp blog is that the text is very small, as the iPhone formatting has been rendered from the original internet content rather than being revised.
To make it legible you really need to either turn the iPhone on its side, or increase the zoom. The iPhone bible also includes a daily reading, and daily reading podcast.