The development of mobile applications today is a complex technological process that requires careful selection of tools. The question of what Android applications are written in is no longer a simple choice between a pair of languages. The modern ecosystem offers many solutions, from native Google tools to cross-platform frameworks. The choice of a specific technology stack directly affects performance, support costs, and speed to market.
For a beginning developer or business planning to create software, understanding the differences between approaches is critically important. A mistake at the language selection stage may lead to the need for a complete rewrite of the code in the future. In this article, we will take a detailed look at the main programming languages, integrated development environments (IDEs) and architectural patterns that dominate the industry right now.
The evolution of programming languages: from Java to Kotlin
Historically, Java has become the foundation of the Android platform. For many years, it was the only officially supported language in which millions of applications were created. Its object-oriented nature and huge library base have made it a de facto standard. However, over time, developers encountered the problem of redundant code (boilerplate code) and some verbosity of the syntax, which slowed down the process of writing apps.
The situation changed dramatically with Google's announcement of language support Kotlin. Running on the Java Virtual Machine (JVM), the language has become the preferred choice for new development. Kotlin addresses many of the shortcomings of its predecessor, offering a more concise syntax and built-in protection against runtime errors, such as the famous NullPointerException. Statistics show that more than 60% of professional Android developers today use this particular tool.
Despite the dominance of Kotlin, it is too early to abandon Java. A huge amount of legacy code (old projects) continues to be maintained and developed. Moreover, for high-load computing or working with low-level equipment, they are often used C++ via JNI (Java Native Interface). This allows you to move critical sections of code into native libraries for maximum performance.
⚠️ Attention: When supporting older Java projects, remember that new Android SDK features can be optimized primarily for Kotlin. Using outdated methods can lead to difficulties when updating the target version of the API.
Integrated Development Environments (IDEs) and Tools
The choice of language is inextricably linked to the choice of environment, in which the work will be carried out. The undisputed leader here is Android Studio. This environment, based on IntelliJ IDEA, provides a complete set of tools for profiling, debugging and testing. It includes emulators for various devices, a visual layout editor and code mining.
For those who work with cross-platform solutions such as React Native or Flutteralternative code editors are often used, for example Visual Studio Code. They are lighter and faster, but require additional configuration of plugins to fully work with the Android SDK. It's important to understand that regardless of the editor, there are still command line tools from Google under the hood, such as adb (Android Debug Bridge).
The process of building projects is controlled by the system Gradle. It is a flexible automation tool that allows you to describe dependencies, library versions, and compilation options in configuration files. It is often difficult for beginners to understand the Gradle syntax, but it is precisely this that ensures the reproducibility of assemblies on different machines.
Use hotkeys in Android Studio: Ctrl+Shift+A allows you to quickly find any action or setting without wandering through the menu.
Cross-platform development: Flutter and React Native
The issue of saving resources often leads teams to the decision to write code once and run it everywhere. This is where cross-platform development frameworks come into the picture. Flutterusing the language Dartrenders the interface independently, bypassing native OS components. This ensures high performance and an identical appearance of the application on any device.
On the other hand, Facebook uses native platform components, wrapping them in JavaScript wrappers. This makes apps look more native to the Android user, but can create performance issues with complex animations. The choice between these approaches depends on the UI requirements and the available expertise on the team. React Native from Facebook uses native platform components, wrapping them in JavaScript wrappers. This makes apps look more native to the Android user, but can create performance issues with complex animations. The choice between these approaches depends on the UI requirements and the available expertise on the team.
Cross-platform has its limitations. Accessing specific hardware functions (for example, complex work with Bluetooth or a camera) often requires writing native modules in Java or Kotlin. Therefore, it will not be possible to completely abandon the knowledge of native technologies in a serious project.
Why is Flutter faster than React Native?
Flutter is compiled into native machine code (ARM or x86) in advance (AOT compilation), while React Native often uses a bridge for communication between the JavaScript thread and native modules, which creates delays.
Comparative table of development technologies
To structure the information and help you make an informed decision, we have prepared a summary table. It reflects the key characteristics of popular approaches to creating mobile software.
| Technology | Language | Performance | Login complexity |
|---|---|---|---|
| Native (Kotlin) | Kotlin | High | Average |
| Native (Java) | Java | High | High |
| Flutter | Dart | Very high | Low |
| React Native | JavaScript/TS | Medium/High | Low |
| Xamarin | C# | High | Medium |
As can be seen from the data, native development on Kotlin remains the gold standard for complex projects that require maximum output from the device. However, for startups and MVP (minimum viable product), frameworks like Flutter can cut development time in half.
⚠️ Attention: Google Play is tightening the size requirements for APK files. Cross-platform applications often weigh more due to built-in engines, which can discourage users with slow Internet.
☑️ Ready for native development
Architectural patterns and modern approaches
Just to know The syntax of the language is not enough. The quality of an application is determined by its architecture. Modern Android development is dominated by an approach divided into layers: Presentation (UI), Domain (business logic) and Data (data sources). This makes it easy to test logic and replace components without rewriting the entire application. Clean Architecture divided into layers: Presentation (UI), Domain (business logic) and Data (data sources). This makes it easy to test logic and replace components without rewriting the entire application.
Reactive programming is increasingly being used to manage interface state and respond to user events. Libraries like Coroutines and Flow Kotlin allows you to work with asynchronous tasks (network requests, database reading) cleanly and safely, without blocking the main interface thread. This is critical for the smooth operation of the application.
It is also worth mentioning the transition to a declarative UI using the library Jetpack Compose. Unlike the old approach with XML markup, Compose allows you to describe the interface directly in Kotlin code. This speeds up development, reduces errors and simplifies the creation of complex animations.
Modern Android developer stack: Kotlin + Jetpack Compose + Coroutines + Clean Architecture.
Publishing and support: what you need to know after writing code
Writing code is only half the journey. The application must go through the process of being built, signed with a digital certificate and published in the store Google Play. To do this, use the developer console, where access rights, descriptions and screenshots are configured. The moderation process can take from several hours to several days.
After the release, the support stage begins. The Android world is fragmented: there are thousands of device models with different OS versions, screen resolutions and memory sizes. It is necessary to monitor crashes using tools like Firebase Crashlytics and promptly release hotfixes.
It is important to monitor changes in store policies. Requirements for data privacy, use of advertising identifiers, and target API level (targetSdkVersion) are updated regularly. Ignoring these requirements may result in the application being removed from the catalog.
⚠️ Attention: Google Play rules and requirements for Android versions change dynamically. Always check the latest conditions in the official documentation of the developer console before releasing a new version, as outdated guidelines may lead to rejection of the build.
What is Target SDK?
This is the version of Android for which your application is optimized. Google requires this setting to be updated regularly to ensure apps take advantage of new security and privacy features.
Frequently asked questions (FAQ)
Is it possible to write Android applications in Python?
Technically yes, using tools like Kivy or BeeWare, but this is not recommended for commercial projects. Such applications are slower, large in size and have limited access to native device functions.
How long does it take to learn how to write applications?
With daily practice (2-3 hours), a basic level that allows you to create a simple application is achieved in 3-4 months. A deep understanding of the architecture and advanced patterns requires a year or more.
Do you need to know mathematics to develop for Android?
For most business applications (stores, social networks, utilities), the school curriculum is sufficient. Higher mathematics is required only in specific areas: game development, computer vision or complex financial algorithms.
What is better to teach a beginner: Java or Kotlin?
Definitely Kotlin. This is a modern standard, the code on it is shorter, safer and more enjoyable to write. Java should be learned only to read old code or if specific corporate standards require it.