Building Mobile Apps with Ionic & Angular is an all-in-one resource for learning the latest and greatest version of Ionic. It has been updated for every major release, so you can rest easy knowing that you're not learning outdated tech.
The organization of the content is not ideal for those who are having the first contact. I recommend prior basic knowledge.
The problem of organization is that it presents a series of concepts in an isolated way and without context, and in the course of the projects these concepts are used, however, without much explanation of that concept. That way, if the reader does not have a basic knowledge, he has to go back to the previous chapters in order to remember.
Nice book but its mostly like an overview of an framework there is some good practice. So its pretty its nice to read if you are starting with the framework or what to know what is new in ionic2.