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Top 23 Kotlin Interview Questions and Answers

29/Sep/2020 | 10 minutes to read

QFLES is listing some Essential Kotlin Interview Questions and Answers for Freshers and mid level of Experienced Professionals prepared by Industry Experts. All answers for these Kotlin interview questions are given based on standard documents and tried to explain in simple and easiest way.

Best Answers to Kotlin Interview Questions

1. Describe Kotlin.

2. What are the advantages and disadvantages of Kotlin?

3. How will you compare Java and Kotlin?

4. What is the difference between fold and reduce in Kotlin?

5. Explain the difference between val and var in Kotlin.

6. In Kotlin, How to deal with nullable values?

7. How to get random number in Kotlin?

8. How to initialize Kotlin's Mutable list to empty Mutable list?

9. What is the equivalent of static method of Java in Kotlin?

10. Explain Lambda (function) in Kotlin.

11. How Property Initialization works in Kotlin? Explain by lazy vs lateinit.

12. Explain Lazy Initialization and Late Initialization.

13. How to initialize a reference variable in Kotlin?

14. How to create a variable without initialization in Kotlin?

15. How to check that a lateinit variable has been initialized?

16. Why kotlin compiler required explicit initialization of var property?

17. Explain delegates in Kotlin.

18. How to access val variable in inner method?

19. What is the difference between List and Array types?

20. What is the difference between val and const in Kotlin?

21. Explain In-line function in Kotlin.

22. Explain string templates in kotlin.

23. Explain format in kotlin string templates?

Some General Interview Questions for Kotlin

1. How much will you rate your self in Kotlin?

When you attend an interview, Interviewer may ask you to rate your self in specific Technology like Kotlin, So It's depend on your knowledge and work experience in Kotlin.

2. What challenges did you face while working on Kotlin?

This question may be specific to your technology and completely depends on your past work experience. So you need to just explain the challenges you faced related to Kotlin in your Project.

3. What was your role in last Project related to Kotlin?

It's based on your role and responsibilities assigned to you and what functionality you implemented using Kotlin in your project. This question is generally asked in every interview.

4. How much experience do you have in Kotlin?

Here you can tell about your overall work experience on Kotlin.

5. Have you done any Kotlin Certification or Training?

It's depend on candidate like you have done any Kotlin training or certification. Certifications or trainings are not essential but good to have.


We have covered some frequently asked Kotlin Interview Questions and Answers to help you for your Interview. All these Essential Kotlin Interview Questions are targeted for mid level of experienced Professionals and freshers.
While attending any Kotlin Interview if you face any difficulty to answer any question please write to us at Our IT Expert team will find the best answer and will update on portal. In case if we find any new Kotlin questions, we will update the same here.

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