Greetings Dev.to community!
Today, I want to spark your interest and motivate you to learn Kotlin in 2025. It's one of my favorite programming languages that combines the best of Java and augments it with modern stuff.
Kotlin - a modern programming language created by JetBrains that’s redefining software development. Let’s explore why learning Kotlin could be the game-changer for your career this year.
What is Kotlin ?
Kotlin is a modern, statically-typed programming language developed by JetBrains, first released in 2011. It runs on the Java Virtual Machine (JVM) and is fully interoperable with Java, meaning you can call Kotlin code from Java and vice versa. This makes Kotlin a perfect choice for developers working within the Java ecosystem who want to take advantage of its modern features without abandoning their existing codebase.
Although Kotlin was initially focused on Android development, it has quickly gained popularity in other areas such as backend development, web development, and even data science. Kotlin’s cross-platform capabilities, especially with Kotlin Multiplatform, enable developers to write shared code that can run on Android, iOS, web, and desktop applications. This versatility has made Kotlin one of the most exciting programming languages of the decade.
In 2017, Google officially announced Kotlin as the preferred language for Android development, further cementing its place as a key tool in the developer's toolkit. Today, Kotlin continues to grow in both popularity and functionality, making it an essential language for developers in 2025 and beyond.
If you’re curious about Kotlin’s history and purpose, JetBrains has shared a detailed overview here.
Easy Integration with Existing Java Projects
One of the standout features of Kotlin is its seamless interoperability with Java, making it incredibly easy to integrate Kotlin code into existing Java projects without requiring a complete rewrite. This is particularly beneficial for companies and developers who want to leverage Kotlin’s modern features while maintaining their existing Java codebase. Here’s how Kotlin makes integration simple:
Full Java Interoperability
Kotlin is designed to work alongside Java, and it can call Java code and vice versa without any issues. This allows you to gradually introduce Kotlin into a Java project without the need for a major overhaul. You can write new Kotlin code for new features or modules, while still maintaining your existing Java code.
Sharing Libraries
Kotlin fully supports Java libraries and frameworks, so you can continue using your existing Java dependencies in Kotlin code. There’s no need to search for Kotlin-specific alternatives - you can take advantage of the vast Java ecosystem while benefiting from Kotlin’s features like null safety, concise syntax, and higher-order functions.
Kotlin-Java Conversion Tools
If you want to quickly convert Java code to Kotlin, the JetBrains IntelliJ IDEA IDE provides a Java-to-Kotlin converter. This tool allows you to automatically convert Java files into equivalent Kotlin code, making the transition even smoother. While manual adjustments may still be needed for complex cases, the converter provides a strong starting point.
Where to use Kotlin
Kotlin’s versatility makes it an ideal choice for a variety of applications beyond its initial focus on Android development. Here are some of the key areas where Kotlin excels:
Android Development
Kotlin has become the preferred language for Android development since Google officially endorsed it in 2017. Its concise syntax, safety features (like null safety), and full interoperability with Java make it the go-to choice for building modern, high-performance Android applications. Major apps like Pinterest, Trello, and Uber have been developed using Kotlin, making it a dominant language in the mobile space.
Backend Development
Kotlin is a fantastic choice for building efficient and scalable server-side applications. With frameworks like Ktor (developed by JetBrains) and Spring Boot, developers can quickly build robust web APIs and backend systems. Its performance, combined with full interoperability with Java, has made it a popular option for large-scale systems at companies like Amazon and Expedia.
Web Development
Kotlin/JS allows developers to use Kotlin for frontend web development as well. By writing JavaScript code in Kotlin, developers can take advantage of a statically-typed language with modern features, making it easier to build and maintain large web applications. Frameworks like React Kotlin Wrappers simplify integration with JavaScript-based libraries and tools.
Data Science and Machine Learning
Although Kotlin is often associated with Android, it’s increasingly being used for data science and machine learning tasks. Libraries like KotlinDL (for deep learning) and krangl (for data manipulation) make Kotlin a competitive choice for these fields. With its strong type safety and seamless integration with the JVM ecosystem, Kotlin is becoming a viable alternative to Python for machine learning tasks.
Cross-Platform Development
Kotlin Multiplatform allows developers to write shared code that works across multiple platforms, including Android, iOS, web, and desktop applications. This feature significantly reduces development time and ensures consistency across platforms. Apps like Netflix and Cash App are using Kotlin Multiplatform to share business logic across their Android and iOS apps.
Command-Line Tools
Kotlin’s simplicity and powerful standard library make it an excellent option for creating command-line tools. Its compatibility with Java means developers can easily integrate existing libraries and create efficient, portable applications.
Kotlin’s wide-ranging applicability makes it an invaluable tool for developers, whether they’re building mobile apps, backend systems, or working on cross-platform projects.
The Job Market for Kotlin Developers
One of the biggest reasons to learn Kotlin is its growing demand in the job market. According to the 2024 Stack Overflow Developer Survey, Kotlin is among the most loved programming languages, especially for mobile development.
In terms of salaries, Kotlin developers are among the highly sought-after professionals in the industry. Data from Talent.com reveals that the average Kotlin developer in the United States earns around $130,813 annually. Entry-level positions start at $115,000, while experienced professionals can command upwards of $160,000 per year.
Companies like Google, Netflix, Pinterest, and Trello are using Kotlin for their Android apps, and its versatility extends to server-side and web development projects as well.
Why 2025 Is the Perfect Time to Learn Kotlin
2025 is an ideal time to learn Kotlin as it continues to gain momentum in the software development world. Kotlin’s prominence in Android development is already well-established, with over 70% of Android developers using it.
The language's interoperability with Java allows for easy integration into existing projects, making it a great option for teams that want to modernize their applications without starting from scratch. As Kotlin’s ecosystem expands, developers also benefit from robust tools, libraries, and frameworks that make it easier to build efficient, scalable apps.
With its versatility, growing demand, and strong community support, Kotlin offers an exciting opportunity for developers looking to stay ahead of the curve in 2025.
I appreciate you taking the time to read this article to the end. If you enjoyed it, feel free to support my efforts with a like! ❤️
Top comments (4)
I am a big fan of Kotlin, but there is no jobs in European market. Only in Android dev, but it's not enough to be master in Kotlin in order to get a job in Android dev.
The only job opportunities in Kotlin it's your offices of Jetbrains in Czechia.
Because it puts the
funin functions !That's true! :)
What do you think about Kotlin ?