But this book really doesn't go there in any effective manner, I'm afraid.
This was partly my fault; I presumed too much about what was going to be covered. The book covers very little in the way of the more subtle and unique aspects of the iPhone: that of being a small format, multitouch device. It barely touches on the user experience issues that, it turns out, Apple discusses at length in their developer
resources.
The biggest issue with the material is inconsistency in level. For example, in one spot it explains how to put to put a slash in a closing HTML tag and in another, takes about the same space to discuss binding event handlers in jQuery. In another place, client side SQL is discussed, but most of space is spent covering generic SQL, which of course is a huge topic.
As to use as a beginning-level reference, I suspect it's so brief as to be hard to follow: it's a short book with a large amount of space taken up by images. I found the code examples to be inconsistent (for example, a mixture of "DOM0", standard DOM, and jQuery) in a way that I would feel uncomfortable exposing a beginner to.
It turns out the book is Creative Commons licensed, so you can read it in HTML if you want. But if you've got a moderate amount of HTML and JavaScript experience, it's going to be too basic and you're better off with blog posts and Apple docs. If those are too advanced, you're probably better off with a generic introductory web app/jQuery book and then off to the more advanced resources.