You can sign up for myBooks by using your Email or Phone. Now you can sign-up myBooks using existing information from a social networking service such as Facebook, Apple, or Google, instead of creating a new login account specifically for myBooks.

myBooks Sign Up Page

myBooks Login Page

Remember me logged in:

The option has added to the login page and it helps the user to keep logged in even when they dint use mybooks for a long time, it will not log out by session time out.