I would prefer to have this in a paper format, for ease of handling. But I must say it works well on Kindle, too.
The author makes it clear this is not a book to teach you grammar, but it's to help guide a fiction writer towards the best way to use (and/or break) the strict rules we were taught at school. Rules which, for the most part, were intended for non-fiction.
I'm particularly fond of his section on the dreaded split infinitive (!) but he makes pertinent remarks about many other issues as well. His explanations of how each piece of grammar actually works are great, but his examples are even better. It's easy to see at a glance how things can be done.
He makes the point that in fiction you can break rules, but that there will be a consequence if they are broken badly, and broken because you don't know any better. I think this is spot-on advice.
This book is useful, pertinent and fun to read. What's not to like?