Manifest Android Interview: The Ultimate Guide to Cracking Android Technical Interviews
As developers, deeply understanding technologies is essential, not just for writing and designing high-quality code, but also for excelling in technical interviews and ultimately joining great teams. However, keeping up with the ever-expanding knowledge in our busy daily lives can be challenging not just for junior developers, but for senior engineers as well.
Many of us have experienced feeling stuck or overwhelmed, especially when preparing for interviews, unsure of where to begin or how to navigate the vast amount of information. This is exactly why the Manifest Android Interview book exists — to help developers who are preparing for upcoming technical interviews or simply looking to deepen and expand their Android knowledge.
Whether you’re aiming to ace upcoming job interviews or deepen your understanding of Android technologies, it’s essential to focus on truly grasping the concepts — not just memorizing answers — and learning how to apply them in real-world projects. In that spirit, this book serves as a practical guide to help you study effectively and prepare efficiently for technical interviews.
Fun facts
Back in mid-2024, I decided to write a book something that had been on my mind for a long time. But turning that intention into action wasn’t easy. I’d heard plenty of stories about how difficult it is to complete a book, and that hesitation delayed me by a month or two. I reached a point where I thought, “If I don’t start now, I might never do it.”
I’ve been maintaining over tens of open-source projects, which made it physically difficult to carve out time. But with that one thought — “I’ll keep putting it off unless I begin today” — I opened a blank Google docs and started writing from scratch.
From that day on, it took exactly 8 months to reach the moment I clicked the “Publish” button. I didn’t miss a single day of writing, even when I was sick on those days, I’d still write for at least 10 minutes. I never lost the momentum or passion for this book. And yes, without a doubt, it was definitely challenging, but also one of the most fulfilling things I’ve ever done, and I sincerely hope this book becomes a valuable resource for the Android community.
Who is this book for?
Manifest Android Interview focuses on Android development, covering the Android Framework, UI (Views), Jetpack Libraries, and Business Logic — as well as Jetpack Compose fundamentals, runtime, and UI. The book features 108 carefully crafted interview questions with detailed answers, 162 additional practical questions, and over 50 “Pro Tips for Mastery” sections.
Whether you’re preparing for technical interviews or simply looking to deepen your Android knowledge, this book offers value regardless of your experience level.
Junior-level
If you’re new to Android development or a junior developer with less than three years of experience, this book may feel slightly challenging at times. However, it can serve as an excellent long-term learning milestone, helping you grasp the core concepts of the Android ecosystem, including fundamentals, UI patterns, and modern Jetpack libraries commonly used in real-world projects.
I wouldn’t call this a “mastery book” that guarantees overnight expertise or brings you to a senior level. Rather, it’s a resource designed to significantly enhance your Android knowledge whether you’re starting from scratch or looking to fill in gaps, but it doesn’t claim to cover every aspect of the vast technical landscape.
Learning is an ongoing journey, and each challenge you overcome makes you a stronger engineer. Whether you’re preparing for your next technical interview or simply striving to deepen your Android expertise, I encourage you to go beyond implementation — understand the why, explore different approaches, and keep learning with curiosity and passion.
Mid-level
If you’re a mid-level developer with a solid foundation and industry experience, this book will help you sharpen your understanding of Android and Jetpack Compose fundamentals while strengthening your problem-solving skills for real-world projects.
Even with 4–6 years of experience, it’s common to use certain APIs daily without fully understanding their inner workings. This book serves as a valuable gateway to deeper technical insight helping you shift your perspective from simply using APIs to truly understanding how and why they work.
Senior-level
If you’re a senior developer with over 7–8 years of experience, this book can still offer valuable insights and a refreshing perspective. In particular, the “Pro Tips for Mastery” sections are a standout — they dive into the internal workings of APIs, explore advanced technical concepts, and share practical wisdom drawn from the author’s experience as a Google Developer Expert.
Ultimately, this book offers meaningful content across all experience levels — from junior to senior — and can serve as a great mental reset, reinforcing and expanding the knowledge you’ve built throughout your career.
Interviewer
If you’re a new interviewer or your team lacks a structured set of interview questions, it can be challenging to determine the right questions to properly evaluate candidates and avoid false positives. This book can serve as a helpful reference, providing interview question ideas that align with your team’s technical specifications, particularly for core systems or frequently used technologies that all team members must be familiar with.
Being a great interviewer is just as important as being a great candidate, as it’s a critical process for selecting future colleagues. I hope this book serves as a valuable resource to help you refine your interview approach and find the best candidates to strengthen your team.
What this book does cover
This book focuses on two primary topics: Android and Jetpack Compose. It covers the essential areas you need to understand and are likely to encounter in technical interviews, making it a strong resource for both learning and interview preparation. The content spans the Android Framework, UI, Jetpack Libraries, and Business Logic, as well as Jetpack Compose, including its Fundamentals, Runtime, and UI components.
Throughout this book, I’ve included footnotes to explain complex terms and concepts, along with visual figures wherever possible to help clarify difficult or abstract ideas. Additionally, the book is packed with practical sample code that you can apply directly in real-world, production-level projects.
What this book doesn’t cover
Initially, I planned to cover everything — from unit testing and Gradle to Kotlin-specific topics. And boom!, the PDF grew beyond 650 pages, and I began receiving feedback that the book felt overwhelming in size. So I revisited and restructured the entire index three times, cutting and cutting again and refining the content until the current version of the book was finally born.
So this book intentionally omits certain topics that aren’t universally required (mandatory) across all companies or teams, such as unit testing, highly specialized third-party libraries, or lower-level hardware features like camera APIs, Bluetooth, or deeply system-level implementations. If you feel that any of these topics are essential for your team, region, or industry, I’d greatly appreciate your feedback. I’m continuously updating and improving the book based on reader input, so your suggestions can directly help shape future editions.
Acknowledgment
I’m deeply grateful to the entire Android community for the support and encouragement throughout the challenging journey of writing this book. A special thanks to Manuel Vivo, Matt McKenna, Alejandra Stamato, and Simona Milanovic for their invaluable feedback and thoughtful comments that helped shape and improve this book 💚
Conclusion
I do believe writing this book is not just a milestone — it’s the first step toward empowering others in the Android ecosystem. The next step is to translate this book into Korean, and potentially other languages. I’m also excited to share that another book is already in the works and scheduled for release later this year.
Learning is a continuous journey, and every challenge you overcome brings you one step closer to mastering your craft. Whether you’re preparing for your next technical interview or aiming to grow as a developer, I encourage you to look beyond implementation, understand the why, explore various patterns and trade-offs, and keep learning with curiosity and passion.
