What are Android Annotations and what are they used for?

Android Annotations is an annotation-driven framework that allows you to simplify the code in your applications and reduces the boilerplate of common patterns, such as setting click listeners, enforcing ui/background thread executions, etc.

I don’t recommend using it; it’s buggy, and unstable. In my current job I am working on a project and my task is to remove Android Annotations. I would suggest using Dagger 2, Butterknife, and RxJava.