Hiring mobile app developers isn’t easy. If you make the right choice, you can get the apps and features you want quickly and easily. If you make the wrong choice, you could face delays, huge cost increases, missing your target windows, and other problems that you should not have to deal with.
Your due diligence is important when hiring mobile app developers. So is asking the right questions. But if you don’t know much about making mobile apps, you might not know what questions to ask.
Here are seven questions you should ask when hiring mobile app developers. I’ve also included follow-up questions for each, to help you dig down to the most important answers.
Mobile apps have become a critical part of most businesses and the demand for skilled mobile developers continues to grow rapidly. As a result, the interview process for mobile developer roles has become extremely competitive.
Doing well and standing out requires thorough preparation and practice. In this article, we’ll overview commonly asked mobile app development interview questions, provide sample answers, and share tips on how to get ready for the recruitment process.
Whether you’re an iOS or Android developer targeting your next career move read on to learn strategies to ace your upcoming mobile dev job interview!
Frequently Asked Mobile Interview Questions and Answers
Here are some of the most common mobile developer interview questions you’re likely to encounter and how to approach answering them
Technical Questions
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How can you store data in Android and iOS? Give examples of different persistent storage options like SharedPreferences, SQLite databases, cloud storage, etc. and when you would use each.
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What are some ways to improve mobile app performance? Suggest compression, caching, optimizing images, not blocking the main thread, profiling to find slow sections, and more. Provide specific examples you’ve used.
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How can you handle background processing in a mobile app? Discuss AsyncTasks, IntentServices, JobScheduler, and WorkManager on Android. For iOS describe Grand Central Dispatch queues and background execution modes like location updates.
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What is the best way for a server to notify an app that some new data is available to sync? Explain push notifications and their pros/cons compared to other options like polling.
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How can you debug your app when it’s already released? Discuss remote logging, crash reporting, debugger statements, overlay debugging UIs, and monitoring user reviews.
Architecture Questions
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How should the client app communicate with backend services? Explain common approaches like REST APIs with JSON data and protobuf over gRPC. Discuss tradeoffs like payload size optimization vs readability.
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Describe Model-View-Controller pattern and where it’s commonly used in iOS apps. Explain how Android Architecture Components like LiveData and Room help separate concerns. Discuss benefits like testability.
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What considerations go into designing the architecture for an enterprise iOS/Android app? Suggest ways to achieve modularity, testability, separation of concerns while optimizing for mobile. Discuss offline support, security, device/OS fragmentation.
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How would you architect a photo sharing social media app? Present an overview of the high level components like cloud storage for photos, feed, realtime messaging, notifications, etc. and how they would connect. Focus on scalability and performance.
Design and Testing Questions
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What types of testing should you perform on mobile apps? Discuss unit, integration, UI, performance, security, localization, accessibility, etc. Explain importance of test automation and mocks for components like network.
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How can you design mobile apps to provide a great user experience? Suggest following platform guidelines, minimizing steps for tasks, intuitive navigation, responsive UI, delight details like animations. Maintain consistency.
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How would you optimize a shopping app for conversions? Discuss guiding users towards key purchase flows while minimizing distractions, prominently featuring offers, smart notifications to re-engage. A/B test variations.
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What considerations go into designing for multiple device sizes and OS versions? Explain responsive layouts, adaptive UI, providing fallback cases, gracefully handling deprecated features and utilizing modern ones when available.
Best Strategies for Preparing for a Mobile Developer Interview
To really excel at a highly competitive mobile app developer interview, you need to put in the time to prepare. Here are some key strategies:
Review Mobile Development Concepts
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Brush up on foundational programming knowledge like data structures, algorithms, design patterns, and SOLID principles. These fundamentals are still relevant.
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Study mobile platform architectures like MVC on iOS and Android Architecture Components. Understand how apps are structured.
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Refresh your memory on REST APIs, JSON, web sockets, push notifications, OAuth, and other common mobile backend interactions.
Practice Mobile Coding Challenges
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LeetCode, HackerRank, and other sites have mobile-focused code samples – practice these regularly.
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Reimplement simple apps from scratch yourself as practice. Focus on good architecture.
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Outline designs for complex app features before writing any code. Think through edge cases.
Rehearse Behavioral Stories
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Prepare STAR stories of projects that show positive outcomes, technical skills, and team collaboration.
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Be ready to speak in detail about the most impressive apps or features you’ve worked on. Quantify results.
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Prepare for questions about challenges faced on past projects and how you overcame them. Show resilience.
Learn About the Company
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Research the company so you understand their business domain, users, competitors, and technical stack. This shows interest.
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Study their flagship apps – be able to comment meaningfully on their architecture and design choices.
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For startups, understand their funding status, leadership team background, and company culture.
Get Plenty of Rest
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Interviews are mentally tiring. Being well-rested will help you stay engaged and positive.
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Sleeping on your interview answers helps strengthen your recall – don’t cram the night before.
With the right combination of technical know-how, behavioral preparation, and research into the company, you will be well-equipped to succeed at your upcoming mobile developer job interview. Best of luck landing your next exciting role developing innovative mobile apps!
What are your fees, rates, and terms?
Listen for how they want to set up the project. Is it time and materials or flat-rate? Be very careful if they want to go flat-rate with you. We always set up projects at Ascendle based on time and materials because it gives you the freedom you need in mobile development, especially if your needs change in the middle of the project.
Follow-up questions:
- If you charge by the hour or a flat rate, why do you do that? What happens if my needs or requirements change during the project?
- How are your fees tied to milestones and performance?
- What if I’m not happy with the project’s outcome or the way it’s going? How are you or we going to fix this?
What are some of the mobile apps you’ve developed?
Obviously, they’re going to tell you about their mobile development “wins” here. That’s good, because you want to know what they consider their wins to be. But when you hire mobile app developers, the most important thing to hear is how their past work fits with yours. Does the company make the connection, or do you have to do it? What mobile apps have they released that you can check out and see for yourself?
Follow-up questions:
- Tell me about a project you worked on that was like ours. Describe how you you completed it from start to finish.
- What apps do you have available in the iTunes Store or the Google Play Store right now? What do other users say about them?
- Tell me about how one of your clients used an app you made, and what happened as a result.
