The Final Version of App Architecture: IOS Application Design Patterns in Swift New Book by Chris Eidhof, Matt Gallagher and Florian Kugler are now available. As with previous objc.io books, I had a small role in the creation of a technical reviewer, a job like I thrive enormously .
I'm obviously biased, but I really recommend the book if you're writing iOS apps. Although you will probably be familiar with some of the architectural patterns discussed in the book, I am sure you will learn something new in each chapter ̵
The book also contains discussions of three experimental architectures. Writing a full iOS app in one of these patterns requires a stronger commitment to deviate from typical UIKit code (sometimes you'll fight against Apple's framework conditions). But the good news is that you do not have to switch the whole app to a new architecture to take advantage of their lessons. Most patterns are based on a relatively small set of core ideas, which can often be used in isolation on existing MVC or MVVM based apps.
In any case, if you have not had the opportunity to try out declarative user interface programming (like React), the book is a good learning opportunity. UIKit's imperative style gets long in the tooth, and I would not be surprised if Apple's rumored cross platform UI project also took inspiration from Elm / React.
Another plus: in just over 200 pages, the book is a relatively fast reading. And if that's not enough, it's an option to buy another 7 hours of video content that complements the book.