Congratulations on completing the last chapter of the book! In this chapter, we saw how useful marble diagrams can be, and we learned to read them. We did that by analyzing the core elements of a marble diagram and then exploring examples for the following operations:

• .map()
• .flatMap()
• .onExceptionResumeNext()
• .groupBy()

It might happen that marble diagrams are not fully clear at first, and it might be a bit too much to rely completely on them. However, they are amazing complementary material that can help clarify certain things that weren't obvious from the description in the documentation.

Also, by now a reader should be able to understand and see the benefits of the RxJava framework and how it helps to write higher-quality code that's easier to maintain. We learned the basic building blocks of the RxJava framework, along with more advanced patterns.

Hopefully, the knowledge presented in this book will allow developers to write much better Android applications that are resistant to the concurrency and threading bugs that plague applications that rely only on standard Android development tools.