A free app for Android, by csdevbin.

Android Interview – Questions and Answers Guide offers a comprehensive collection of questions and answers that covers everything that you need to know about the Android operating system. It is perfect for app developers or IT professionals who are preparing for job interviews.

The app contains unit wise and flow charts that will help you understand the system well. The interview questions are arranged in many categories, ranging from the basic to the advanced. You will be able to learn concepts from categories such as broadcast receiver, content provider, intent, fragments, SQLite, user interface, storage, and more. 

It is designed to provide users a convenient way to review the Android operating system.