In this chapter, we talked about build types, product flavors, and all their possible combinations. These are very powerful tools that can be used in any application. From a simple setup with different URLs and keys to more complicated apps that share the same source code and resources but have different branding and several versions; build types and product flavors can make your life considerably easier.

We also talked about signing configurations and applying them, and mentioned a common pitfall when signing product flavors.

Next, you will be introduced to multimodule builds. These are useful when you want to extract code into a library or a library project, or when you want to include, for example, an Android Wear module into your app.