How to write an email reader books from mobile devices, which will differ from analogues in the impossibility of exporting the book itself?

Question

Electronic books

There are several author's books that are available only to a certain category of users. We need to write a reader application that can open these books without any problems, and offline, but these files should not exist separately from the application. In short, what is required in the application:
1. The ability to read books offline
2. The book must be loaded into the application itself so that there is no book file
3. Access to a particular book must be carried out using device identification
Is this even real? With what to do? We need at least some tutorial on writing your own readers.

Answer 1

I put the monitor on the scanner. Your turn ;)