Does this book cover using databases, send to and retrieval? If so, what database program types? I have had a course in Android programming. The instructor did not want to use a book in the class and we were left with just the use of the Android site. Several times I found the site hard to understand, sometimes not. Is your book user friendly?
Databases are not a big subject on Android, IMO, at least not nearly as big a topic as they are in web or enterprise apps. Either the built-in SQLite covers your needs, or you will likely resort to a server-based DB accessed through a REST API.