Hiring a Flutter Developer: Essential Interview Questions

hiring a flutter developer

After considering several options available, you have decided to create a cross-platform application on Flutter. You should then hiring a skilled flutter developer.

Interview Questions When Hiring a flutter developer

There are two different ways to go about this:

  1. Hire Flutter developer(s) and include them in your team– This option grants you complete control over your employees regarding salaries, working culture, and business processes. 
  2. Contact a software development company and let them handle every process involved– It is an excellent option because you don’t have to bring everything up from scratch. Software development companies have convincing track records, handle all organizational tasks, and are guided by best practices. 

You should take your time to hire the right people if you settle for Flutter developers. How to go about that? Look for these developers in the right places and remember to ask the right questions. We have listed examples of questions to ask when hiring a Flutter developer. These questions will help you assess their skills and knowledge.

General Questions

You should start with general questions to get the conversation going. These questions will help you understand more about a specific candidate and why they opted for Flutter development.

Q1. What is Flutter?

A: It is an open-source, cross-platform user interface framework released in 2017 by the giant tech company Google. It can create excellent user interfaces on iOS, Android, and Web platforms. Flutter uses Dard coding language

Q2. What are the benefits of Flutter?


  • HotReload– The platform increases development speed and creates room for easy experimenting.
  • Growing Popularity– Flutter ranks second among popular cross-platform networks at the moment. Its community is also growing each new day.
  • Appealing Design and Visuals– Flutter has many widgets to customize and support heavy animations and graphics.
  • Quality Performance– Flutter boasts of a high FPS compared to other cross-platform frameworks and minimal dropped frames. It has the best architectural solutions. It’s hard to notice the difference between Flutter and native applications.

Q3. Give me a list of some of the most popular apps made using Flutter

A: Stadia, Tencent, eBay, Groupon, Baidu, Reflectly, and many more.

Theoretical Questions

After the general questions, you should proceed to more questions that will help you know if the developer understands how Flutter apps are built and the functioning of their components.

Q4. Define the difference between imperative and declarative programming?

A: The developer writes code explaining the expected result in declarative programming. In imperative programming, the developer gives the compiler a step-by-step guide of what is expected to happen.

Q5. Explain the step-by-step guide of writing a Flutter application?


  1. Create a starter app or simple template app
  2. Put in an external package. Also referred to as ‘english_words,’ it contains English words and utility functions, which you should use.
  3. Include a stateful widget. This helps to keep the state of a widget.
  4. Set up an infinite scrolling ListView– utilize the RandomWordState expansion to generate and show a word pairing list.
  5. Create profile runs– This helps to evaluate the performance of an app.

Q6. What can be referred to as the building blocks of a Flutter app?

A: Widgets are the key elements or building blocks of a Flutter application’s user interface (UI). Each widget is a fixed declaration of a section of the user interface.

Q7. State the difference between stateless and stateful widgets?

A: A widget is stateful if it can change (for example, after users interact with it). Stateless is used to refer to app interactions that never change.

Q8. What does a Spacer Widget do?

A: It develops an empty spacer that you can use to create spacings between widgets with limited heights and widths.

Q9. Why does a Flutter app take long to run for the first time?

A: It takes too much time to load the accurate dependencies and configuration for a specific version.

Q10. What is the role of Flutter’s hot reload feature?

A: Hot reload grants you the opportunity to implement changes to an app very fast. After making changes to the code, it will update the app immediately. This is vital in speeding up the development process and simplifying experiments.

Q11. Is multithreading supported on Dart?

A: Dart programs run separately. It is a single-threaded programming language.

Q12. Which Integrated Development Environments (IDEs) does Flutter use? What’s your perfect choice and why?


  • Emac
  • Visual Studio
  • Codemagic
  • Android Studio
  • IntelliJ Idea

Q13. Name the modes you can use when developing a Flutter app?


  • Profile Mode- To evaluate the performance
  • Debug Mode- Supports Hot Reload and is widely used when developing an app.
  • Release Mode– Widely used to deploy an application. It minimizes footprint size and optimizes an app.

Q14. What are the List Views available in Flutter? Mention ListView constructors and their key differences?

A: The number of List Views available is four:

  • ListView- Mostly used during the development process.
  • ListWheelScrollView– Creates an effect of things revolving on a wheel.
  • AnimatedListView– Animated a specific item when removed or inserted.
  • Recordable List View- Grants you the chance to re-arrange items through dragging and dropping.

The number of List View contractors available is two:

  • ListView.builder- This constructor is meant for fixed lists. It is ideal for pagination and long lists. The items created by this constructor are only visible on the screen.
  • ListView– A constructor that is mainly used for small lists. Not ideal for long lists.

Q15. Describe the Keys in Flutter?

A: These are parameters that control the state of widgets when you move them in a widget tree. They also control the widgets that link up with others after rebuilding.

Q16. Describe Const in Flutter?

A: It is a keyword to announce constants. You can modify variable values that are declared with const. The keyword represents a compile-time constant and develops an item during compilation before inserting it where it is needed.

Q17. What are Await and Async?

A: They are keywords used to describe nonsynchronous functions. You should add async before the function body to define it. The await keyword only works in async functions.

Q18. Explain how to use a stream in Dart? Describe the functions


  • Dispose- This is to cancel the subscription
  • Listen- to subscribe to a stream

Q19. Name the databases you like using with Flutter and Why?


  • SQLite – has an embedded SQL database and does not need a separate server process.
  • ObjectBox – object-oriented database for IoT and mobile devices.
  • Firebase– smooth data browsing, NoSQL real-time database
  • Moor – reactive persistence library on SQLite
  • Hive – completely native to Dart, offline storage for NoSQL.

Q20. Explain Navigator in Flutter?

A: It manages screen navigation and the routes. It also keeps the app widgets stack.

Q21. Explain the role of Scaffold in Flutter?

A: It provides the default structure properties (floating action button, appbar, drawer, and many more). You don’t have to set up a new custom structure for the screen, app activity, page, or user interface view.

Q22. Name the Flutter architectural patterns that are widely used

A: Redux, BLoC, mobx, mwwm

Q23. What is the difference between mainAxisAlignment and crossAxisAlignment?


  • mainAxisAlignment is a property that defines the alignment of items on the main axis, which appears vertical in a column and horizontal in a row.
  • crossAxisAlignment is a property defining how elements align on the other axis( horizontal in a column and vertical in a row).

Practical Questions

Once you evaluate the theoretical knowledge of a developer in Flutter, you should give them a few practical tasks. Good theory with no practical coding qualities is not valuable for an app development project.

Q24. What does this method do? What does it do in its current state?

flutter method

A: The role of this function is to insert spaces in big numbers. There are wrong names in the variables.

flutter variables

Q25. What is this code’s output?

flutter code output

A: The console output does not match the code’s consecutive lines, and there will be a change in the order:

Step 1.3

Step 2.2

Step 3.4

Next Steps

Our interview questions can help you during the first stage when assessing a candidate. If you still have doubts after that, you can give the developer a home task. You can ask them to do a code review for an already-existing app or write one for a simple app. This will give you an idea of how they handle complex tasks.

You should not forget to ask them about their interests, goals, and soft skills. Some of the skills to look out for in a developer include:

  •   Emotional stress tolerance and communicative skills
  •   The appetite for learning new things
  •   Independent and quick thinking

Final Words

Hiring a flutter developer or more for a new business may prove to be somewhat tricky. A lot of time and money is required in the hiring process, especially if the app is critical to your business model. Trust your task with experts for a successful project.