Realm: Building Modern Swift Apps with Realm Database (Second Edition)

This is a good reference book for learning how to use Realm properly. It includes some information that just isn't found online, and it also pulls all of the information into one handy place. I was disappointed in the quality of the printing, because the book is one of those just-in-time printing services that is printed and shipped as soon as you order it. It looks like it was printed on cheap paper using a laser-printer that is low on toner.