Have you ever wondered how those millions of applications that you download from Google Playare created? Behind each icon on the screen of your smartphone are hundreds of lines of code written in different programming languages. But what exactly are the technologies that underlie modern Android applications? Why do some developers choose Kotlin, while others choose Flutter or even C++?

In this article we will analyze in detail all the current methods of creating applications for Android, from classic Java and Kotlin to cross-platform solutions like React Native. You will learn which tools are suitable for beginners, and which giants like Google or Netflix use for their flagship products. And most importantly, you will understand how the choice of language affects performance, development speed, and even how much space your application will take up in the phone’s memory.

Spoiler: there is no universal “best” language - it all depends on the task. But after reading, you will be able to confidently answer the question: “What to write mine Android application on?".

1. Official Android languages: Java and Kotlin

Google officially supports two languages ​​for developing native Android applications: Java and Kotlin. At the same time since 2019, Kotlin has been declared the preferred language for Android - this means that all new tools and libraries from Google are primarily optimized for it.

Java - this is the “grandfather” of Android development. Most older applications are written on it, including systems Google (for example, Gmail or YouTube). Its main advantages:

  • 🔹 Stability: decades of development, a huge community and millions of ready-made solutions for Stack Overflow.
  • 🔹 Compatibility: works on all versions Android, including outdated ones (up to API 16).
  • 🔹 Multi-platform: Java code can also be used for the backend (for example, Spring Boot).

However, Java also has disadvantages. For example, verbose syntax (you need to write a lot of “extra” code for simple tasks) and slow compilation compared c Kotlin. The latter was created by JetBrains specifically to eliminate these problems.

Kotlin is a modern alternative to Java that is fully compatible with it (you can use both languages in one project!). Its advantages:

  • 🔹 Conciseness: the same functionality is achieved in 2-3 times less code.
  • 🔹 Security: in Kotlin they occur less often NullPointerException (the most common error in Java).
  • 🔹 Modern features: coroutines for asynchronous programming, feature extensions, smart castes.
⚠️ Attention: If you are just starting to learn Android development, Google recommends starting with Kotlin. All official tutorials and documentation are now written in it. However, knowledge Java is still useful for supporting legacy code (legacy projects).

Example code in Java and Kotlin for the same task (message output):

// Java

public class MainActivity extends AppCompatActivity {


@Override


protected void onCreate(Bundle savedInstanceState) {


super.onCreate(savedInstanceState);


setContentView(R.layout.activity_main);


TextView textView = findViewById(R.id.textView);


textView.setText("Hello, Android!");


}


}

// Kotlin

class MainActivity : AppCompatActivity() {


override fun onCreate(savedInstanceState: Bundle?) {


super.onCreate(savedInstanceState)


setContentView(R.layout.activity_main)


textView.text = "Hello, Android!"


}


}

📊 Which language would you choose for your first Android applications?
Java
Kotlin
Not decided yet
Other

2. Native development: C and C++ for high performance

When it comes to applications that require maximum performance (for example, 3D games, video editors or AR/VR), C and C++come to the rescue. These languages allow you to write code that runs almost at the hardware level, which is critical for computation-intensive tasks.

Main use cases C/C++ in Android:

  • 🎮 Game engines: Unity (uses C# + C++ under the hood), Unreal Engine (entirely in C++).
  • 📹 Video/audio processing: Applications like Adobe Premiere Rush or VLC use C++ for media decoding.
  • 🤖 Machine learning: libraries like TensorFlow Lite have a C++ kernel for accelerating neural networks.

For integrating C/C++ code into an Android application used Native Development Kit (NDK). This is a set of tools that allows you to compile native code into binary files (.so), understandable Android. However, working with NDK requires deep knowledge and has its pitfalls:

⚠️ Attention: Use of NDK increases the size of the application (due to additional libraries) and can lead to compatibility problems on different processor architectures (ARM, x86, x86_64). Google recommends resorting to NDK only if native code is really needed.

Example of project structure with C++:



my-app/


├── app/


│   ├── src/


│   │   ├── main/


│ │ │ ├── java/ # Java/Kotlin code


│ │ │ └── jni/ # C/C++ code


│   │   │       ├── native-lib.cpp


│   │   │       └── CMakeLists.txt


│ └── build.gradle # NDK configuration

Unless you plan to develop games or super-productive applications, most likely C++ will be enough; you won't need it.. For most tasks, Kotlin/Java.

💡

Before using NDK, check whether the problem can be solved using Android Jetpack or RenderScript —they often provide sufficient performance without complicating the code.

3. Cross-platform development: Flutter and React Native

What if you want to release an application not only on Android, but also on iOS, Web or even Windows and at the same time write the code once? This is where cross-platform frameworks come to the rescue. The two most popular: Flutter (from Google) and React Native (from Meta).

Flutter uses the language Dart and renders the interface independently (without native components), which gives high performance and the same appearance on all platforms. Its pluses:

  • 🎨 Flexible UI: you can create any design, not limited to standard elements Android/iOS.
  • ⚡ Hot Reload: changes in the code are applied instantly, without restarting the application.
  • 📦 Rich ecosystem: a huge number of packages on pub.dev.

React Native, in turn, uses native components of the platform. This means that the interface will look “native” for JavaScript and native platform components. This means that the interface will look "native" to Android or iOS, but there may be performance problems with complex animations. Advantages:

  • 👨‍💻 Easy entry: if you know JavaScript, mastering React Native is easier than Kotlin.
  • 🔄 Updates without the App Store: you can update the JS code on the fly (via CodePush).
  • 🌍 Large community: millions of developers and tons of tutorials.

Comparison of Flutter and React Native:

Criterion Flutter React Native
Language Dart JavaScript/TypeScript
Performance Higher (rendering via Skia) Lower (bridge between JS and native code)
UI components Native (the appearance is the same on all platforms) Native (look like standard Android/iOS elements)
Popularity Growing (used Alibaba, BMW) Higher (used Facebook, Instagram)

Which framework to choose? If maximum performance is important to you - take custom design - take it FlutterIf you already have a team JavaScript developers or need to quickly prototype an MVP - React Native.

💡

Cross-platform frameworks save time and money, but native applications (on Kotlin/Java) are still the leaders in performance and integration with system functions.

4. Alternative approaches: Python, Lua and others

Although Kotlin, Java and C++ dominate the Android world, there are also less obvious ways to create applications. For example, Python can be used using a framework. Kivy or BeeWare. This is convenient for:

  • 🐍 Script automation: if your application is a wrapper over a Python script (for example, for data analysis).
  • 🎓 Training: Python is easier for beginners than Java/Kotlin.
  • 🔬 Prototyping: quickly build an MVP without a deep dive into the Android SDK.

However, Python has serious limitations:

  • ⚠️ Low performance compared to native languages.
  • ⚠️ Large APK size (due to the inclusion of a Python interpreter).
  • ⚠️ Limited access to the Android API (not all system functions available).

Another exotic option is Lua (used in the game engine Love2D). It is suitable for simple 2D games, but not for full-fledged applications. Example code in Lua for Love2D:

function love.draw()

love.graphics.print("Hello, Android!", 400, 300)


end

Also worth mentioning C# s Xamarin (from Microsoft). This is another cross-platform framework, but it loses Flutter and React Native in popularity. Its main advantage is access to the ecosystem .NET.

⚠️ Attention: If you choose an alternative language (Python, Lua, C#), be prepared for the following:

—you will have to solve compatibility problems manually;

—the community will be smaller, and documentation is more sparse;

— Google Play can block applications with non-standard runtimes (for example, if they use outdated versions of Python).

5. Development tools: Android Studio, IDE and SDK

No matter what language you write in, you can’t do without the right tools. The main development environment for Android is Android Studio (from Google). It includes:

  • 🛠️ Integrated Environment (IDE) with support Kotlin, Java and C++.
  • 📱 Android Emulator for testing on different OS versions and screen sizes.
  • 🔍 Profilers for performance analysis (CPU, memory, network).
  • 🤖 Android SDK - a set of tools for assembly and debugging.

Alternatives Android Studio:

  • 💻 Visual Studio Code + plugins (for example, Flutter or React Native Tools). Suitable for cross-platform development.
  • 🍎 Xcode (only for macOSif you are developing under iOS).

Important components Android SDK:

Component Purpose
Android SDK Platform Libraries for a specific version of Android (for example, API 34 for Android 14).
Android SDK Build-Tools Tools for compiling code (for example, aapt2, dx).
Android Emulator Virtual devices for testing.
Google Play Services API for integration with services Google (maps, authorization, advertising).

An example command for installing the necessary components via sdkmanager:

sdkmanager "platforms;android-34" "build-tools;34.0.0" "emulator" "platform-tools"

For cross-platform development, additional tools may be needed:

  • 🦋 For Flutter: Flutter SDK and plugin for Android Studio/VS Code.
  • ⚛️ For React Native: Node.js, npm/yarn, Watchman.

Install Android Studio|Download the latest Android SDK|Set up an emulator or connect a physical device|Install Git for version control|Select a language (Kotlin/Java) and create the first project-->

6. Which language should you choose for your project?

The choice of language or framework depends on several key factors. Let's look at them in order.

1. Application type:

  • 📱 Simple application (for example, To-Do list): Kotlin or Flutter.
  • 🎮 Game: C++ (with Unreal Engine) or C# (with Unity).
  • 📊 Application with complex logic (for example, financial analysis): Kotlin + native modules for C++.
  • 🌍 Cross-platform solution (Android + iOS + Web): Flutter or React Native.

2. Your experience:

  • 👶 Beginner: start with Kotlin (official support Google) or Flutter (easier for visual tasks).
  • 👨‍💻 Experienced developer:
    • If you know Java —go to Kotlin.
    • If you know JavaScript —try React Native.
    • If you know C++ — use NDK for critical parts.

3. Performance requirements:

  • ⚡ Maximum performance: native development on Kotlin/Java + C++ (where needed).
  • ⏳ Acceptable performance: Flutter (better than React Native).
  • 🐢 Prototype or MVP: can be used Python (for example, Kivy).

4. Budget and deadlines:

  • 💰 Limited budget: cross-platform solutions (Flutter/React Native) will save time and money.
  • ⏰ Tight deadlines: Flutter allows you to develop UI faster than native tools.
  • 🏆 Long-term project: native development on Kotlin will pay off in the future (easier to maintain and scale).

If you are still in doubt, answer these questions:

  1. Do I need the application Only for Androidor should it work on other platforms?
  2. Does my team have experience with Kotlin/Java or JavaScript/Dart?
  3. Is maximum productivity required (for example, for games or video processing)?
  4. What is my budget and terms?
What did large companies choose?

Google (most applications) - Kotlin
Facebook - React Native (but partially switch to native code)
Alibaba — Flutter
Netflix - Kotlin + native C++ modules for video
Ubisoft (games) - C++ with Unreal Engine

Technologies do not stand still, and what is relevant today may be outdated in a couple of years. What trends should be taken into account when choosing a stack for Android development?

1. Kotlin Multiplatform (KMP)
JetBrains is actively developing Kotlin Multiplatform a technology that allows you to write general logic for Android, iOS, Web and even Desktop in one language. Unlike Flutter or React Native, here only the backend code is common, and the UI is written natively. This gives better performance and integration with the platform.

2. Compose Multiplatform
Jetpack Compose (native framework for UI on Kotlin) now works not only on Android, but also on iOS, Desktop and Web. This means that soon it will be possible to write a completely native cross-platform UI without compromises in performance.

3. The move away from Java
Google is gradually phasing out support Java in favor of Kotlin. Already, new features Android SDK appear first for Kotlin, and Java versions may lag behind. In the future, Java may remain only for legacy projects.

4. The growing popularity of Flutter
Flutter continues to gain momentum due to its performance and flexibility. In 2026 Google announced Flutter 3.16 with improved support Android 14 and new widgets for Material You (dynamic design in style Android 12+).

5. AI and ML in mobile development

Integration artificial intelligence becomes easier thanks to tools such as:

  • 🤖 TensorFlow Lite (for running neural networks on the device).
  • 🧠 MediaPipe (from Google, for processing video and gestures).
  • 🗣️ On-device speech recognition (speech recognition without sending data to the server).

6. Strengthening security requirements
Google Play tightens the rules for applications:

  • 🔒 Mandatory use Android App Bundle (AAB) instead of APK (reduces the size of the application).
  • 🛡️ Requirements for data encryption (for example, mandatory use of data encryption If you plan to publish an application in HTTPS).
  • 📱 Restrictions on access to personal data (you need to explain why you need CAMERA or LOCATION).
⚠️ Attention: If you plan to publish your application to Google Play, stay tuned requirements for the target version of the SDK. From August 2026, all new applications must support Android 14 (API 34), and from November 2026, updates to existing applications must also meet this requirement.

FAQ: Frequently asked questions about Android development

🔹 Is it possible to write Android applications in Python?

Yes, but with reservations. For this, frameworks like Kivy, BeeWare or Chaquopy (plugin for Android Studio). However, such applications:

  • Will work slower than native ones;
  • Take up more space (due to the inclusion of the Python interpreter);
  • May not support all Android features.

Python is suitable for prototypes or scripting tasks, but not for full-fledged commercial applications.

🔹 Which language is easier for beginners to learn?

The simplest options:

  1. Flutter (Dart) - if it is important for you to quickly see the result and do cross-platform application.
  2. Kotlin — if you want to learn the “official” language for Android and are not afraid to dive into native development.
  3. React Native (JavaScript) — if you already know JS or plan to develop for it as well iOS.

The hardest part will be C++ (due to low-level features) and Java (due to verbose syntax).

🔹 How long does it take to learn how to write Android applications?

Time depends on your experience and goals:

  • 📱 Simple application (for example, a calculator): 1-3 months with intensive training.
  • 💼 Commercial project (with backend, database, authorization): 6–12 months.
  • 🎮 Complex application (game, video editor): 1–2 years (requires study C++ or game engines).

Tip: start with the official tutorials from Google (Android Basics in Kotlin) and write your own small projects at the same time.

🔹 Is it possible to make money on Android applications?

Yes, but the market has changed a lot in recent years. Main methods of monetization:

  • 💰 Paid applications —it is difficult to compete with free alternatives.
  • 📺 Advertising (via AdMob, Facebook Audience Network) - the most popular method.
  • 🛒 In-app purchases (for example, premium features in games).
  • 🏦 Subscriptions (for example, in fitness applications or business services).

Average income depends on the niche:

  • Games: from $1,000 to $100,000+ per month (if the project is successful).
  • Utilities (calculators, weather): $100–$5,000 per month.
  • Niche applications (for example, for doctors or engineers): $5 000–$50,000 per month.

Important: Google Play takes 15–30% from income (depending on