Software development for the Google mobile platform has undergone tremendous changes in recent years. If a decade ago the de facto standard was a single language, today the developer faces a difficult choice from a variety of tools and technologies. The question of how to write a native application for Android has ceased to be rhetorical and requires a deep analysis of the project requirements, team qualifications and desired performance.
Modern ecosystem Android Studio offers unprecedented flexibility, allowing you to combine different approaches within one project. However, it is the choice of the main programming language that determines the architecture of the entire future product, the speed of its writing and the ease of further support. To fail at this stage is to lay the foundation for technical debt that will take years to pay off.
In this article, we will take a closer look at the current technology stack options, from classic solutions to cutting-edge methodologies, so that you can make an informed decision for your next project.
Java: A classic that fades into history
For a long time Java remained the uncontested king of mobile development. Millions of lines of code in existing applications are written in this language, and it is impossible to completely abandon it in the next decade. Many large banking systems and corporate solutions continue to function due to reliability and predictability Java Virtual Machine.
However, the use of Java for new projects in 2026 raises more and more questions. The language has excessive verbosity, which increases the time it takes to write code and increases the likelihood of routine errors. Developers have to write significantly more boilerplate code compared to modern alternatives to implement the same logic.
However, knowledge of Java is critical to support legacy code. If you plan to work with large enterprise projects that have been in development for more than 5-7 years, you cannot do without this skill. In addition, the Java community is huge, and it is not difficult to find ready-made solutions for any problems.
- 📦 A huge ecosystem of time-tested libraries and frameworks.
- 🛡 Strict static typing helps to catch errors at the compilation stage.
- 📚 Abundance of documentation and educational materials accumulated over 20 years.
⚠️ Attention: Google officially announced the priority of Kotlin several years ago. New APIs and platform features are primarily optimized for Kotlin, and Java support may become secondary in future versions of the Android SDK.
Kotlin: Industry standard and Google's choice
Today Kotlin is the preferred language for Android development. It is a modern, concise and safe language that is fully compatible with Java, but without its main disadvantages. Google has made a bet on Kotlin, and now almost all official documentation and code examples are provided in it.
The main advantage of Kotlin is its ability to prevent a whole class of common errors, such as NullPointerException, thanks to its nullable type system. This allows you to write more stable code that crashes less often in production. The language syntax allows complex ideas to be expressed in a few lines, which significantly increases readability and speed of development.
In addition, Kotlin supports functional programming, which opens the door to using reactive approaches and working with data streams. Integration with Jetpack Compose a modern declarative UI kit is possible only through Kotlin, which makes it the only choice for creating modern interfaces.
The transition from Java to Kotlin is usually painless due to full interoperability. You can call Java code from Kotlin and vice versa, allowing you to migrate your project gradually, module by module, without stopping the development of new features.
Use JetBrains' online code converter to quickly convert existing Java classes to Kotlin. This will save hours of manual work, but be sure to check the result as the logic may require manual modification.
C++ and NDK: When maximum performance is important
In situations where the standard capabilities of the Android virtual machine are not enough, developers turn to Native Development Kit (NDK) and the C++ language. This approach is justified only in specific scenarios where every millisecond of CPU time is critical or direct access to hardware is required.
Using C++ complicates the process of building an application and debugging. You'll have to work with two languages at the same time, managing memory manually and risking subtle bugs like memory leaks or heap corruption. An error in the native code often leads to an instant crash of the entire application without the possibility of recovery.
However, for certain categories of applications this is the only way. Game engines, complex video or audio processing algorithms, cryptographic calculations and work with external peripheral devices often require a native implementation. In these cases, the overhead of the Java/Kotlin runtime becomes unacceptable.
| Criteria | Kotlin / Java | C++ (NDK) |
|---|---|---|
| Development speed | High | Low |
| Performance | Sufficient for 95% of tasks | Maximum |
| Memory safety | Automatic (Garbage Collector) | Manual control |
| APK size | Standard | Increased due to libraries |
Why you shouldn’t write the entire interface in C++?
Trying to implement UI logic in C++ via the NDK will deprive you of all the benefits of automatic memory management and modern UI debugging tools. You will gain productivity in tasks that are not critical for the interface, but you will lose several times in development speed.
Tools: Android Studio and ecosystem
The choice of language is inextricably linked with the choice of an integrated development environment. Android Studio, based on IntelliJ IDEA, is an industry standard and provides the best support for Kotlin and Java. Built-in refactoring tools, static code analysis and device emulators make the process of creating applications as comfortable as possible.
For working with C++, Android Studio has a built-in full-fledged LLDB debugger and a code editor with syntax highlighting CMake. However, setting up build scripts build.gradle and CMakeLists.txt can be a real challenge for a beginner. Incorrect configuration of library paths or compilation flags often leads to linking errors that are difficult to diagnose.
It is important to note that the ecosystem around Kotlin is evolving much faster. Jetpack libraries such as Room, WorkManager and Navigation have first-class Kotlin support using coroutines and flows. Using these same libraries with Java requires writing more binding code and using outdated patterns.
When creating a new project, the creation wizard in Android Studio suggests Kotlin by default. Removing this option requires additional steps and manual configuration of templates. This is a clear signal from the community and vendor about where the industry is heading.
☑️ Checking environment readiness
Architectural patterns and modern approaches
The programming language itself does not guarantee the success of the project. Choosing the right architecture is critical. Modern Android development is dominated by the MVVM (Model-View-ViewModel) and MVI (Model-View-Intent) approaches. These patterns help separate application logic, interface and data, making the code testable and maintainable.
Using Jetpack Compose changes the paradigm of creating interfaces from imperative to declarative. Instead of finding elements by ID and changing their properties, you describe how the UI should look depending on the current state. This fits perfectly with the functional style of programming in Kotlin.
For dependency management and service injection, Hilt or Koinhas become a standard. These frameworks make it easy to manage the life cycle of objects and avoid rigid coupling between application components. Properly setting up a DI container from the very beginning will save you from a lot of problems when scaling your project.
⚠️ Attention: Don't try to implement all the business logic inside an Activity or Fragment. This will create a "God Object" that will be impossible to test and maintain. Move the logic into separate UseCase or Repository classes.
Final choice of development strategy
To summarize, we can say that for 99% of new projects the only reasonable choice is a bundle Kotlin + Jetpack Compose. This stack provides the best balance between development speed, performance, and code security. The investment in learning Kotlin will pay off immediately, as you will write less code and spend less time debugging.
Java should be considered only in two cases: if you are supporting a very old project or if your entire team consists of experienced Java developers who are not ready to retrain, and deadlines are running out. But even in this case, a gradual migration of new modules to Kotlin is recommended.
Leave C++ and NDK for highly specialized tasks. Unless you're writing an Unreal Engine game or a real-time signal processing application, you probably won't need to dive into the depths of manual memory management.
Start a new Kotlin project using Jetpack architectural components. This will ensure that the code is up to date for the next 5-7 years and will simplify the search for developers to join the team.
The mobile development market is dynamic, and the requirements for applications are growing. Choosing the right tools at the start is the foundation on which the success of your product will be built. Don’t skimp on code quality for the sake of immediate gain, because rewriting an application from scratch is many times more expensive than initially using modern standards.
Is it possible to completely abandon Java in a new project?
Yes, you can write 100% of the application code in Kotlin. Moreover, this is the recommended approach. All necessary libraries and SDKs have Kotlin support, and interaction with system APIs is carried out natively.
How difficult is it to learn Kotlin if I know Java?
The transition takes from several days to a couple of weeks. The syntax is similar, but the concepts are different. The main difficulties arise with coroutines and advanced functions, but documentation and conversion tools help a lot.
Does the choice of language affect the size of the final APK file?
The difference is minimal. Kotlin adds a small runtime library, but thanks to the ProGuard and R8 mechanism, which remove unused code, the final size of the application is practically the same as the Java version.
Is it worth learning C++ for Android development for a beginner?
No, it’s not worth it. First, master Kotlin and the basics of mobile architecture. C++ is needed only in narrow niches. Learning it unnecessarily will only slow down your entry into the profession and complicate your understanding of the basic principles of the platform.
What is Jetpack Compose and is it necessary to learn it?
This is a modern toolkit for creating UI. It is mandatory to learn it for new projects, since the classic approach with XML is gradually becoming a thing of the past. Compose significantly speeds up the layout and makes the interface code more understandable.