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Kotlin Onboarding: Introduction

Learn Kotlin by building games and apps from day one—no setup stress, real-time hints, and step-by-step guidance.

Beginner
6 days

You'll take this course in your JetBrains IDE.
Just install JetBrains Toolbox 2.7+, and we'll handle the rest!

Beginner
6 days

About

Kotlin is a modern, industry-trusted language known for its clean, beginner-friendly syntax.

This course is designed for absolute beginners and structured into short, focused modules with clear milestones and built-in IDE learning guidance.

You’ll start coding immediately and progress project by project—from your first playable console app to the classic Hangman game and a final visual pattern generator.

Your result: writing real Kotlin code in professional tools, with the confidence to keep going.

Content

  1. Kotlin Onboarding - Welcome!
  1. Story twister - Introduction
  2. Story twister - Program Entry Point
  3. Story twister - First Kotlin Program
  4. Story twister - Built-in Functions
  5. Story twister - Start the Game
  6. Story twister - Variables, Theory
  7. Story twister - Variables, Practice
  8. Story twister - Read user input, Theory
  9. Story twister - Read user input, Practice
  10. Story twister - Comments
  11. Story twister - Complete the Project
  1. Chat - Introduction
  2. Chat - Ask First Question
  3. Chat - Ask Second Question
  4. Chat - Complete The Project
  1. Mastermind - Introduction
  2. Mastermind - Types of Variables
  3. Mastermind - Variables for Game Settings
  4. Mastermind - Custom Functions
  5. Mastermind - Functions as Expressions
  6. Mastermind - TODO function
  7. Mastermind - Add First Custom Functions
  8. Mastermind - isComplete Function
  9. Mastermind - Loops
  10. Mastermind - Mutable Variable
  11. Mastermind - Play Game Function
  12. Mastermind - Run Game
  13. Mastermind - Conditional Operator
  14. Mastermind - Conditional Operator as Expression
  15. Mastermind - Finish isComplete Function
  16. Mastermind - Basics About Collections
  17. Mastermind - Lambda Expressions
  18. Mastermind - countExactMatches Function
  19. Mastermind - countAllMatches Function
  20. Mastermind - countPartialMatches Function
  21. Mastermind - printRoundResults Function
  22. Mastermind - Boolean Operators
  23. Mastermind - isWon Function
  24. Mastermind - isLost Function
  25. Mastermind - Composite If Operators
  26. Mastermind - Break Expression
  27. Mastermind - Finish Base Game
  1. Mastermind Advanced - Introduction
  2. Mastermind Advanced - Random Function
  3. Mastermind Advanced - joinToString Function
  4. Mastermind Advanced - generateSecret Function
  5. Mastermind Advanced - Error Handling
  6. Mastermind Advanced - isCorrectInput Function
  7. Mastermind Advanced - safeUserInput Function
  8. Mastermind Advanced - Finish The Game
  1. Hangman - Introduction
  2. Hangman - isComplete Function
  3. Hangman - generateNewUserWord Function
  4. Hangman - generateSecret Function
  5. Hangman - getHiddenSecret Function
  6. Hangman - isCorrectInput Function
  7. Hangman - safeUserInput Function
  8. Hangman - getRoundResults Function
  9. Hangman - Finish The Game
  1. Console Photoshop - Introduction
  2. Console Photoshop - Multi Row Strings
  3. Console Photoshop - trimPicture Function
  4. Console Photoshop - Filter Functions
  5. Console Photoshop - when Expression
  6. Console Photoshop - error Function
  7. Console Photoshop - applyFilter Function
  8. Console Photoshop - lines Function
  9. Console Photoshop - repeat Function
  10. Console Photoshop - StringBuilder
  11. Console Photoshop - applyBordersFilter Implementation
  12. Console Photoshop - applySquaredFilter Implementation
  13. Console Photoshop - null Value
  14. Console Photoshop - Null Safety
  15. Console Photoshop - safeReadLine Function
  16. Console Photoshop - chooseFilter Function
  17. Console Photoshop - let Scope Function
  18. Console Photoshop - choosePicture Function
  19. Console Photoshop - getPicture Function
  20. Console Photoshop - Finish The Application
  1. Patterns Generator - Introduction
  2. Patterns Generator - getPatternHeight Function
  3. Patterns Generator - fillPatternRow Function
  4. Patterns Generator - repeatHorizontally Function
  5. Patterns Generator - dropTopLine Function
  6. Patterns Generator - canvasGenerator Function
  7. Patterns Generator - canvasWithGapsGenerator Function
  8. Patterns Generator - Finish The Application
  1. Survey

Note

This course does not provide a detailed explanation of the basic concepts, like variables: it just shows how to use them in Kotlin and can briefly remind you of the definitions.

Learn with the tools developers use every day

Real-world development environment (Python)
Project-based learning journey (Python)
Collaboration via Git (Python)
Focused learning (Python)
  • Real-world development environment

    Gain hands-on experience with the same tools and workflows you'll use in your career, reducing the learning curve when transitioning to real-world projects.

  • Project-based learning journey

    Our plugin is designed to guide you through real coding projects that you can showcase in your portfolio after completion.

  • Collaboration via Git

    Easily track changes and collaborate on projects using Git — an essential tool for developers in every field.

  • Focused learning

    Enjoy fewer distractions with assignments, coding, debugging, and version control all in one window

Student? Get JetBrains IDEs & hands-on courses — free for the full duration of your studies.

What do you need to start?

1

Install the free JetBrains Toolbox App

The JetBrains Toolbox App 2.7+ makes setting up your course effortless. Already have a compatible IDE? It will launch it. If not, the app will install the right IDE for your course.

Learn more about our licenses here.

Download

JetBrains Toolbox App illustration
2

Confirm the course launch

Click Take course and then Allow to open the Toolbox App.

Select Always Allow to skip this confirmation in the future.

To return to the course later, find it in your IDE's recent projects.

Need more help? Check out our guide.

Course launch confirmation illustration
JetBrains Toolbox App illustration

The JetBrains Toolbox App 2.7+ makes setting up your course effortless. Already have a compatible IDE? It will launch it. If not, the app will install the right IDE for your course.

Learn more about our licenses here.

Download

JetBrains Toolbox App illustration

Click Take course and then Allow to open the Toolbox App.

Select Always Allow to skip this confirmation in the future.

To return to the course later, find it in your IDE's recent projects.

Need more help? Check out our guide.

JetBrains Toolbox App illustration

FAQ and troubleshooting

Yes, you will need the JetBrains Toolbox App and a JetBrains IDE.

Just click this link to install the JetBrains Toolbox App. We've taken care of all the necessary settings, and the app will handle the rest of the setup for you.

The JetBrains Toolbox App checks which IDE is compatible with your course and whether it is installed on your computer. If you have the necessary IDE installed, the app will open it. If not, JetBrains Toolbox will initiate the installation, prioritizing free community editions.

Yes, the JetBrains Toolbox App is essential, even if you already have a JetBrains IDE. It automatically prepares your IDE for studying by installing the required plugins and updating the IDE if necessary.

Please make sure you have the latest version of the JetBrains Toolbox App. To update, open the app and click Update Toolbox App, or download the latest version here.

If you’re using a Chrome-based browser, please also allow Find devices on local networks in the popup that appears on the course page. When this permission is granted, the page will detect when the Toolbox App opens on your system and you’ll be able to open the course properly.

Yes! It's 100% free and works with both the free and paid versions of JetBrains IDEs.

If you're a student, apply for the Student Pack to get full access to JetBrains IDEs for the duration of your studies. If not, check if you qualify for a free non-commercial license.

    • Enable the Kotlin plugin:
    • Go to Settings/Preferences | Plugins | Installed.
    • Make sure that the Kotlin plugin is enabled.
    • Add an SDK:
    • From the main menu, select File | Project Structure | Platform Settings | SDKs.
    • To add an SDK, click +, select the necessary SDK, and specify its home directory in the popup dialog.
    • Download JDK (if needed):
    • If you don't have the necessary JDK on your computer, select Download JDK.
    • In the next dialog, specify the JDK vendor and version, change the installation path if required, and click Download.

For more information, see our Help article.

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The course requires the latest installed version of Toolbox application. If you don’t have it, you can download it here.

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