5 best languages for Android app development

8 min read
August 21, 2023

Which language should I use?”

Android developers are always faced with this question when starting out.

If you don’t know yet, there are actually multiple programming languages you can use to build an Android app. Each has its own pros, cons, and use cases.

The first step in deciding which to use is to get to know each a little bit better. And that’s what this article will help you with.


Java holds a special place in Android development because it has been the OG language ever since Google acquired Android in 2005.

There’s a reason for this—Java is one of the most well-loved programming languages in the world.

It’s consistently at the top of the TIOBE Index, a ranking of over 256 languages based on popularity and usage.

Top programming languages

Source: Cleveroad

This popularity gives Java developers a significant advantage. It’s a well-established language with a rich ecosystem of libraries, frameworks, and tools.

Plus, thousands of experts worldwide are familiar with the language, so you’ll always get the help you need.

Java is also one of the first true cross-platform languages with its write once, run anywhere approach.

As long as the platform has the Java Virtual Machine (JVM) or something equivalent, it can execute Java code.

Java virtual machine

Source: Educba

But probably Java’s biggest edge is its security and stability. The JVM provides an extra layer of security that prevents any malicious code from executing.

This layer also enhances performance through mechanisms like memory management and garbage collection.

It’s why Java is the preferred language for building enterprise and mission-critical software.

However, the main drawback of Java is the significant overhead of running the JVM.

Even though the Android Runtime (ART) has improved Java’s performance over the years, the overhead is still there.

Java is also notorious for being verbose, which means you’ll likely write longer code with lots of boilerplate. Its syntax is also less expressive.

All of this could prolong development and testing time.

These shortcomings are understandable, as Java is an aging language that has existed for almost three decades.

It’s why Google pushed for more modern languages to eventually replace Java—like Kotlin.


Kotlin is, in many ways, the step in evolution that follows Java. No surprise there, as Kotlin itself is derived from Java but with significant improvements.

The most significant change is conciseness. Kotlin improves upon Java’s verbosity, allowing developers to implement ideas with fewer lines of code.

In fact, Java code can be reduced by an average of 40% when rewritten in Kotlin.

Here’s a side-by-side comparison.

Kotlin vs. Java

Source: Ace Infoway

Kotlin also improves on many aspects of Java’s performance.

For example, Java is notorious for Null Pointer Exception errors. This is when the code executes a variable with a null value.

In Java, null is a non-value that could create unexpected results or crash the software if handled improperly. It’s even recognized as a security vulnerability by OWASP.

Indeed, it’s why many call this error the Billion Dollar Mistake.

But Kotlin largely bypasses this error thanks to its null safety feature. The compiler immediately alerts the possibility of a null pointer so the developer can fix it immediately.

Null Safety in Kotlin

Source: Dave Leeds from Type Alias on Twitter

But probably the best thing is that Kotlin is interoperable with Java, as Kotlin code is compiled into bytecode that also runs in the JVM.

You can also easily convert Java to Kotlin in Android Studio.

Thus, moving to Kotlin from Java isn’t a big leap but a gradual transition. If you’re not fully committed, you can do it in steps.

Of course, there are a few caveats you should consider when making the switch.

One is that Kotlin isn’t 100% compatible with Java at the moment. There will still be some Java libraries, tools, or SDKs that won’t work properly when ported to Kotlin.

Kotlin is also a newer language with a smaller, less mature ecosystem. That means fewer third-party plugins, tools, or templates that can speed up your development.

Nevertheless, these drawbacks are minor at best and will improve over time as Kotlin becomes more streamlined.


C++ is hands down one of the most powerful and versatile languages today.

In fact, Android is just a small subset of its use case. It’s used to build everything from cutting-edge 3D games to operating systems.

If the program is complex and advanced, chances are it’s built with C++.

Now, it’s important to note that C++ isn’t a native Android language. To use it, you’ll need to convert the code using the Android Native Development Kit (NDK).

This allows your Java or Kotlin code to access the converted C++ code.

As such, C++ is meant as a supplement to Android languages.

It’s often used to implement performance-critical components, such as game engines, real-time audio, and computationally-intensive tasks.

And that’s because C++ is one of the fastest programming languages ever.

Unlike Java, C++ is compiled into machine code that runs directly on the underlying device without runtime machines or interpreters.

The lack of an intermediary reduces overhead significantly, making it execute faster in certain cases.

C vs. Java

Source: Scientific Research

The drawback of C++’s power is its notorious learning curve.

C++ is perhaps one of the most difficult languages to learn.

Its syntax is less readable or intuitive than that of modern languages like Swift or Python, making it particularly challenging for beginners.

Furthermore, C++ gives you all the power, including memory manipulation and management.

This requires a deep understanding of the syntax, which makes programmers much more prone to errors.

Nevertheless, if your Android app requires advanced features like 3D processing or scientific computations, C++ can be a good complement.


To start, C# is used the same way as you could in C++. You’ll need to use the Android NDK.

That’s because C# isn’t native to Android Studio, nor does Google support it directly. Consequently, it’s rarer in Android development than C++.

Alternatively, you can use C# via Xamarin, the cross-platform mobile development tool in Microsoft Visual Studio.

Xamarin.Android uses C

Source: Xamarin Android Guide

The main reason you’ll use C# is if you’re already familiar with it.

As a C# developer, you can leverage your existing skills to build Android apps without learning a new language. This speeds up the learning curve dramatically.

Furthermore, you can use many of the libraries, tools, and frameworks you’ve already learned.

You can also capitalize on Visual Studio’s extensive debugging and programming toolset to further speed up your work.

This ability is especially useful if you want to port software from one platform into Android.

Of course, there are trade-offs.

One is that C# and Visual Studio aren’t optimized for creating mobile apps. Thus, their features won’t be as applicable as those of Android Studio’s toolset.

Plus, remember that Android development with C# isn’t as common. That means you’ll have a smaller community of developers to consult with if you ever encounter problems.

Because of these reasons, C# is, at best, a niche Android development language reserved for mid-level apps. For anything complex, Java or Kotlin might be a smarter alternative.


Dart is the proprietary language of Flutter, Google’s cross-platform mobile app development tool.

The language itself is very easy to learn, which is one of its strengths. Dart uses English-like syntax that’s intuitive to read and understand, similar to modern languages like C# or Javascript.

Thus, Dart makes for an easy switch for an expert or a great gateway for the beginner.

Dart makes for an easy switch for an expert or a great gateway for the beginner

Source: GitHub

One of the powerful features of Dart is the hot reload. This capability allows developers to edit the code and see changes in real time.

As you can imagine, this speeds up development dramatically by eliminating the time-consuming write-compile-test-edit cycle.

Dart is also surprisingly fast for a cross-platform language. That’s because Dart code is compiled into native Android code, resulting in good performance and smooth animations.

But for all its advantages, Dart has one glaring weakness—the file size.

One study concluded that Dart’s file sizes can be 14 times larger than Java or Kotlin.

To test it, the researcher created the same app using different languages.

The resulting Java code (the first photo) clocked in at 539 KB, while Dart (the second photo) was at a whopping 7.5 MB!

Source: Medium

Nevertheless, Dart can be a great alternative if you want to build cross-platform apps as fast as a native Android app.

What’s the best language to use?

As you finish this article, you might ask yourself—what’s the best Android programming language on this list?

The answer is that it depends.

It depends on your situation, skill level, project, constraints, and budget. The important thing is to use the programming language that best fits your requirements.

But what if your team needs to use a language it doesn’t know how to use?

That’s where partnering with an experienced team like DECODE comes in handy.

With a pool of over 100+ developers, we’ll always give you a dedicated team with the right skills for your project.

Interested? Get in touch today, and let’s talk!

Written by

Ivan Trogrlic

Android Team Lead

An Applied Sciences graduate and a true connoisseur of tech, Ivan is a software developer with a genuine love for exploring new technologies. QAs love his code, and his fellow developers always value his input. For Ivan, there is no issue too small to talk over, and no problem that can’t be solved together. When he is not coding, Ivan is usually hiking or playing football. His ideal workspace? Probably a cottage in the mountains, with a serious gaming setup and fast internet connection.

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