Application Developer interview questions and answers
These sample Application Developer interview questions will help you test technical skills and identify qualified candidates for your roles. You can also use our Boolean cheatsheet template to source professional App Developers.
10 good application developer interview questions
- What features would you change/implement to an application to make it faster?
- Do you have an idea of an app or feature that our customers would enjoy?
- How would you ensure the application you’re designing will scale to fit multiple screen sizes?
- What would you do if you discovered that a feature you designed had made the application run more slowly?
- Which programming languages are you mostly familiar with?
- What interfaces do you choose to create a user-friendly application?
- How do you minimize security risks?
- What steps do you take to migrate an application from one platform to another?
- What are the main differences between web and mobile applications?
- How do you troubleshoot a crashing application?
Here are 10 essential interview questions and sample answers to help identify the best candidates for this role.
1. What features would you change/implement to an application to make it faster?
This question assesses the candidate’s understanding of application performance optimization.
Sample answer:
“I would look into reducing the number of HTTP requests, optimizing images, and implementing lazy loading to improve the application’s speed.”
2. Do you have an idea of an app or feature that our customers would enjoy?
This question gauges the candidate’s creativity and understanding of user needs.
Sample answer:
“Based on your customer base, I think a personalized recommendation feature would greatly enhance user engagement.”
3. How would you ensure the application you’re designing will scale to fit multiple screen sizes?
This question tests the candidate’s knowledge of responsive design.
Sample answer:
“I would use media queries and flexible grid layouts to ensure the application is responsive and scales well on various screen sizes.”
4. What would you do if you discovered that a feature you designed had made the application run more slowly?
This question evaluates the candidate’s problem-solving skills and accountability.
Sample answer:
“I would first identify the bottleneck through performance profiling and then optimize the code or algorithm responsible for the slowdown.”
5. Which programming languages are you mostly familiar with?
This question assesses the candidate’s technical skills and expertise in specific programming languages.
Sample answer:
“I am most proficient in JavaScript, Python, and Java.”
6. What interfaces do you choose to create a user-friendly application?
This question gauges the candidate’s understanding of user experience design.
Sample answer:
“I prefer clean and intuitive interfaces, often using Material Design guidelines for Android and Human Interface Guidelines for iOS.”
7. How do you minimize security risks?
This question tests the candidate’s knowledge of application security.
Sample answer:
“I follow best practices like input validation, secure data storage, and implementing proper authentication and authorization mechanisms.”
8. What steps do you take to migrate an application from one platform to another?
This question assesses the candidate’s experience with platform migration.
Sample answer:
“I would start by evaluating the compatibility issues, then refactor the codebase, and finally test rigorously on the new platform.”
9. What are the main differences between web and mobile applications?
This question evaluates the candidate’s understanding of different application platforms.
Sample answer:
“Web applications are accessed via a web browser, while mobile apps are native to a particular operating system. Mobile apps often have access to device-specific features.”
10. How do you troubleshoot a crashing application?
This question tests the candidate’s debugging skills.
Sample answer:
“I would start by checking the error logs, then isolate the issue through debugging tools, and finally fix the code causing the crash.”
What does a good application developer candidate look like?
A strong Application Developer candidate should have a solid grasp of programming languages, an understanding of user experience design, and the ability to think critically and solve problems. They should also be adaptable and have a genuine interest in staying updated with the latest technologies.
Red flags
Be cautious of candidates who lack problem-solving skills, have poor communication abilities, or seem disinterested in continuous learning. These could be indicators of a poor fit for an Application Developer role.
Application Developer Interview Questions
Application Developers work with one or more programming languages and operating systems to design functional programs. Their role is to understand user requirements and build features that meet these needs.
Depending on the seniority level of the position, you may want to look for candidates with several or few years of work experience. For example, for junior positions, a degree in Engineering/Computer Science along with a relevant internship may be enough to qualify for the role. For a senior-level role, look for candidates with solid experience in the Software Development Life Cycle (SDLC.)
As with all technical roles, it’s best to use a written assignment to test candidates’ coding skills. Also, keep an eye out for potential hires who are passionate about their field and take on side projects. They’re more likely to contribute fresh ideas, inform their team about new tools and perform well at work.
Let’s summarize some of the questions and add a few more divided into specific types.
Operational and Situational questions
- What features would you change/implement to an application to make it faster?
- Do you have an idea of an app or feature that our customers would enjoy?
- How would you ensure the application you’re designing will scale to fit multiple screen sizes?
- What would you do if you discovered that a feature you designed had made the application run more slowly?
Role-specific questions
- Which programming languages are you mostly familiar with?
- What interfaces do you choose to create a user-friendly application?
- How do you minimize security risks?
- What steps do you take to migrate an application from one platform to another?
- What are the main differences between web and mobile applications?
- How do you troubleshoot a crashing application?
Behavioral questions
- What’s your area of expertise and what would you like to learn more about? Why?
- Are you currently involved in a side project? If so, what is it? If not, what kind of project would interest you?
- Which of the applications you’ve created are you mostly proud of? Why and what was your role in the development team?
- What are your favorite mobile apps and why?