14 Best Programming Languages for App Development to Use

Developers often ask themselves one key question: what is the best language for app development? The answer depends on the app’s nature and its target platform. Mobile apps generally fall into three groups: native, hybrid or cross-platform, and progressive web apps (PWAs). Each type works best with certain programming languages. This guide explains which languages suit each situation, for both Android and iOS native apps.

Types of Mobile Apps

It is possible to label modern mobile applications into three categories. The knowledge of such types is crucial in determining the programming language of your choice when developing an app:

Native Apps

Native applications are created on a particular platform (Android or iOS) and are developed in a platform-specific language. App stores download these apps and they have the best performance and user experience. Android native apps are normally coded in Java or Kotlin, and iOS native applications in Swift (previously Objective-C).

Native apps are written in the platform’s preferred language, allowing them to use all device features. However, they require more time and money to build. Each platform needs its own codebase, which lengthens development and raises maintenance costs.

Hybrid Apps/Cross-Platform Mobile Apps

Hybrid/cross platform apps seek to have a single codebase across platforms. Basically, hybrid applications are web applications encased in a shell. They are frequently written using common web languages (HTML5 and CSS and JavaScript) and distributed on app stores. The popular hybrid frameworks have developed into advanced cross-platform solutions. As an example, React Native enables the programming of mobile applications in JavaScript and Flutter uses Dart. These strategies reduce both the development time and cost through platform sharing of code.

Nevertheless, it can be accompanied by performance trade-off: a hybrid application can be a bit slower or less refined than a native application. Nevertheless, cross-platform frameworks have become much better, and such companies as Instagram, WhatsApp, and Uber use them successfully.

Progressive Web Apps (PWAs)

Progressive Web Applications are basically mobile-friendly web applications that act as applications. PWAs operate within the browser but can be installed in a device and operate offline with resources that are stored in caches. They are developed with web technologies, usually modern web frameworks, HTML, CSS and JavaScript. PWA may be opened immediately by clicking on a URL, without installing an app store. This facilitates updates and maintenance (a single codebase to all platforms, just like a web site).

PWAs benefit from search engine indexing because they function as web pages. However, they have limited access to device features, especially on iOS, which restricts many PWA functions. They cannot fully replace native apps for capabilities like Bluetooth, advanced camera functions, or certain push notifications. Even so, PWAs are a strong choice for building cross-platform experiences quickly. They are now widely used for news sites, e-commerce stores, and simple utilities that don’t require native-level performance.

Best Language for Android App Development

Officially, two languages, Kotlin and Java, are supported by Android. The most appropriate decision will be based on your project requirements. Nevertheless, Kotlin has become very popular with new projects in Google. Kotlin is used by more than half of professional Android developers. A brief description of the two languages is given below:

Kotlin (with Features, Pros, Cons)

Kotlin is a statically-typed modern language created by JetBrains. It is an official Android language announced in 2017 and since 2019 Google has declared Android development as Kotlin-first. Features: Kotlin is interoperable with Java, i.e. it is possible to mix Kotlin and Java within the same project. It has brief syntax, null safety (to prevent null-pointer bugs), extension functions, coroutines to write asynchronous programs, and numerous contemporary conveniences.

• Pros: Kotlin’s concise syntax reduces boilerplate, making code shorter and less error-prone than Java. It has built-in null safety to prevent common crashes. Kotlin is highly productive – 67% of developers reported increased productivity with Kotlin. It’s officially supported by Google, with many Android libraries and Jetpack APIs now offered in Kotlin versions first. Kotlin is also growing in popularity. In Stack Overflow’s 2023 survey, about 59% of Android developers used Kotlin, slightly ahead of Java at 53%. This suggests that Kotlin has become the default choice for Android development. Its strong interoperability also makes it easy to migrate legacy Java apps while still using the large Java ecosystem.
• Cons: The major weaknesses of Kotlin are connected with its relative youth. It also has a limited developer community than Java, which implies that there are fewer learning resources and examples on niche problems. Kotlin has great build tools and IDE support, particularly because Android Studio is optimized to use Kotlin. However, according to some developers, there are situations when compilation is slower than Java. New syntax and concepts are also presented by Kotlin, and they may lead to a learning curve. Nevertheless, these disadvantages do not significantly outweigh the advantages of Kotlin to the majority of developers. Nowadays, it is frequently regarded as the most suitable language to be used in Android development of apps.

Java (with Features, Pros, Cons)

Android apps were initially and exclusively written in Java before the emergence of Kotlin. It is an object-oriented language that has been in use in enterprise software decades. Features: Java is executed on the Java Virtual Machine (JVM), and is write-once-run-anywhere portable. Android is built on a version of the JVM and therefore Java code executes to Android devices in the form of a bytecode. Android is not the only Java ecosystem with a large number of libraries and frameworks.

• Pros: Java is enormous with a community and a maturity. Almost any problem that a developer may be facing has large documentation, forums and libraries. It is a mature ecosystem, which implies that Android is Java-compatible with a plethora of third-party tools and SDKs. Java has a good performance that is due to decades of optimization it runs large scale enterprise systems and even the Android APIs themselves. It’s also versatile. Indicatively, a Java Android developer can transfer the competence to back-end development.
• Cons: Java has been accused of being verbose – in Kotlin, a task can be compact in the number of lines; in Java, it can take numerous lines. Such wordiness can retard the growth and create additional opportunities of mistakes. Java also does not have modern language constructs provided by Kotlin.

Best Language for iOS App Development

The iOS platform of Apple has its major languages of Swift and Objective-C, and in some cases, it uses C++. Swift is the modern language which has been introduced in 2014 in Apple and is now used in nearly all development of iOS. We will look at Swift, Objective-C and the place of C++.

Swift (with Features, Pros, Cons)

Swift is a type-safe, high-speed language which Apple developed to replace Objective-C. It has rapidly become the most popular programming language used in the apps on the iOS as it is fully supported by Apple and adopted by the developer community. Features: Swift is a clean and expressive language that resembles Python/JavaScript more than the verbose Objective-C. It has contemporary paradigms: Safety: optionals and type inference, generics, closures, and an extensive standard library. The swift code is translated into native machine code to provide high performance. It also added SwiftUI (declarative UI framework) to make interface construction easier.

• Pros: Swift has a high performance and development rate. Apple states that Swift-written applications may be 2.6 times faster than Objective-C objectives in some tasks. The safety properties of the language (such as optional to avoid null references) ensure a reduced number of crashes at the runtime. The terse syntax used by Swift reduces the boilerplate and enhances readability which is good when maintaining. One other significant strength is the commitment on the part of Apple: Apple continually enhances Swift and gives it dense documentation and tooling.
• Cons: Swift being a relatively new language has undergone numerous revisions with some of them introducing breaking changes. Even though it has been stable over the past few years, developers still have to refresh their code sometimes to support new versions of Swift or iOS SDKs. Swift is also not based on cross-platform. It is also compatible with Apple, and it is not feasible to use it with Android or other systems. In the case of cross-platform applications, frameworks such as Flutter or React Native are still superior.

Objective-C (with Features, Pros, Cons)

The heritage language used to develop iOS and macOS is Objective-C which dates back to the 1980s. It is an extension of C, with object-oriented facilities and a Smalltalk-like messaging syntax. Features Objective-C is made up of header (.h) and implementation (.m) files and it is dynamically dispatched at runtime. It is a superset of C, which means that it can be integrated with C/C++ libraries. Most of the fundamental Apple structures (such as UIKit) were coded in Objective-C, and it was the predominant Apple language up until the release of Swift.

• Pros: Objective-C is a stable, highly-tested technology that has been in use decades. An enormous amount of extant code, and tutorials exists in general – someone has remarked that there is an answer to almost every Objective-C query at Stack Overflow. This is a comfort in terms of troubleshooting legacy projects. Due to its superset nature with C, Objective-C can freely interact with C and C++ code. It is useful when an application requires the inclusion of low-level libraries or game engines in C/C++.
• Cons: Objective-C has fallen behind Swift in many areas. Its syntax is clumsy and verbose, filled with brackets and older conventions that feel unfamiliar to developers from other languages. It also lacks Swift’s compile-time safety, so issues like null pointers or string errors often appear only at runtime. Because the language is older and now largely replaced by Swift, many of its libraries and tools are no longer actively maintained.

C++ (with Features, Pros, Cons)

C++ is not a primary language for standard iOS app development, but it still plays an important role in certain cases. Many mobile apps, especially games, use C++ for core logic or engine code, and this code can be compiled for multiple platforms. Features: C++ is a high-performance systems language with manual memory management, pointers, and several programming paradigms, including procedural, object-oriented, and generic programming with templates. On iOS, developers can mix C++ with Objective-C in Objective-C++ (.mm) files, allowing C++ code to work alongside Apple’s frameworks.

• Pros: The major benefit of C++ in mobile applications is performance. Tasks that are computationally intensive, algorithms or graphics rendering can be executed faster in C++ than in higher-level languages. Code written in C++ is also platform-portable – e.g. the engine of a game may be C++ on Android and iOS, with the user interface only written in Kotlin/Java or Swift/Objective-C. That is why C++ is appealing to cross-platform game development (such engines as Unreal Engine are written in C++).
• Cons: C++ spans both high- and low-level programming, so most developers find it impractical to build an entire mobile app with it. It also lacks the rapid development features found in newer languages. iOS and Android do not offer native UI toolkits for C++, meaning developers must wrap platform APIs or use cross-platform UI frameworks. As a result, building user interfaces in C++ is slow and difficult. In practice, C++ is used mainly for core logic, while the UI and app layers are written in platform languages.

Best Language for Cross Platform App Development

Cross-platform development allows building apps for Android and iOS from one codebase. Several languages and frameworks enable this. The best language for cross-platform mobile app development will depend on the framework you choose. Here we highlight five popular choices:

JavaScript (React Native) (with Features, Pros, Cons)

JavaScript is the language of the web and with react native it also became a significant force in mobile app development. React Native is an open-source project by Facebook that utilizes JavaScript (frequently with the React framework) to make mobile UIs. Features: React is developed in JavaScript/JSX, and React Native is translated into native UI elements. The application logic is implemented on a JavaScript engine, which interacts with native modules. This enables the use of web development skills on mobile. It is worth noting that React Native allows the use of TypeScript (a typed superset of JavaScript) to ensure more reliable code, but the runtime remains JavaScript.

• Pros: React Native has real cross-platform UI elements, which allow a developer to write once and use on both Android and iOS. This significantly minimizes the work of multi-platform application. JavaScript is dynamic and loosely typed, hence developers can code fast. The massive size of the web community makes it easy to migrate to React Native by a number of developers. The pool of talent is also big on JavaScript which has been the most popular programming language over the years.
• Cons: JavaScript is a dynamic language and thus it may cause runtime errors that would have been detected earlier on in a more traditional language such as Java or Swift. TypeScript assists through the addition of static types, however, it needs additional configuration. Most UI-based applications have good performance, but intensive JavaScript computations can be slow and require native modules or background processing. The JavaScript-native code interface may also be complex. In case your application is based on heavy custom native functionality, you will still find yourself developing platform-specific modules.

Dart (Flutter) (with Features, Pros, Cons)

Google uses Dart as the language behind Flutter. Flutter has become a popular option for cross-platform development. Features: Dart is an object-oriented, strongly typed language with syntax familiar to Java and C# developers. Both the UI layout and application logic in Flutter are written in Dart, and the final apps are compiled into native ARM code. Flutter does not rely on native UI elements. Instead, it renders everything using its high-performance Skia graphics engine. This allows Flutter apps to deliver consistent UI and performance across platforms.

• Pros: Flutter offers near-native performance and a rich UI toolkit. Because it controls every pixel on the screen, apps can achieve smooth animations and flexible designs on both Android and iOS. Flutter also supports hot reload, letting developers apply code changes in milliseconds. Dart is easy to learn, especially for Java or JavaScript developers, and is designed for productivity. A major advantage is that one Dart codebase can target mobile, web (via Dart-to-JS), and even desktop. This makes Flutter highly versatile.
• Cons: Flutter apps tend to have larger file sizes because the framework ships with its own rendering engine. This is fine for most apps but can be limiting for very lightweight projects. Dart is also less well-known than JavaScript, so teams may face a learning curve when adopting Flutter. Since Flutter doesn’t use native widgets, it can be slower to update when Android or iOS introduces new UI components, as the Flutter team must implement their own versions.

C# (Xamarin/.NET MAUI) (with Features, Pros, Cons)

C# is a Microsoft-created language traditionally used for Windows applications and back-end services. With Xamarin—and now .NET MAUI—C# can also be used to develop cross-platform mobile apps. Features: Xamarin allows developers to write shared C# code that is cross-compiled into native ARM binaries. Native APIs are accessed through C# wrappers. Xamarin’s successor, .NET MAUI (Multi-platform App UI), provides a unified way to build apps for Android, iOS, Windows, and macOS using C# and .NET.

• Pros: C# has the benefit of familiarity and good code reuse to developers who are already in the Microsoft/.NET ecosystem. C# code can be used to share business logic with mobile applications even desktop applications. Xamarin and.NET MAUI equally have access to all native device APIs via a single syntax, meaning that one can do virtually anything in C# that they would do in Java or Swift. There is also good performance. Under Xamarin with modern .NET optimizations and AOT compilation, most apps can be run nearly as fast as native code. The second advantage is the extensive.NET Standard library ecosystem and the extensive variety of NuGet packages in popular features.
• Cons: Xamarin traditionally had a smaller community than React Native or Flutter, even with Microsoft’s backing. This meant fewer UI libraries and extensions, though many of these gaps have been filled over time. Xamarin and MAUI apps can also have noticeably larger file sizes because the runtime and libraries are bundled into the binary. Start-up time was a concern in earlier versions as well, but recent updates have improved performance.

Python (Kivy, BeeWare) (with Features, Pros, Cons)

Python is one of the world’s most popular languages thanks to its simplicity and readability. While it is not a typical choice for mobile UI development, frameworks like Kivy and BeeWare make mobile development in Python possible. Features: Kivy is a cross-platform GUI toolkit built on OpenGL, allowing the same Python code to run on Android, iOS, Linux, and more. BeeWare is a set of tools that lets developers define native UIs in Python using libraries like Toga, which then translate those definitions into native widgets on each platform. Python is an interpreted, dynamically typed language, making it quick and easy to develop with.

• Pros: The main advantage of Python for app development is developer productivity and ease of learning. Python’s syntax is very beginner-friendly – often recommended as the best language for app development for beginners when starting with simple projects. With Python, one can leverage an enormous range of libraries for everything from scientific computing to web services. This makes Python appealing if your app has heavy data processing or AI components (since Python is dominant in AI/ML coding). Python’s popularity is immense: it’s consistently ranked among the top two or three languages globally (in 2025 it nearly matched JavaScript in usage), and it’s considered the go-to language for machine learning and AI across surveys.
• Cons: Python has a disadvantage in mobile scenario in terms of performance and platform integration. Python is also interpreted (or interpreted by a code-ulator) and thus tends to be slower than compiled languages such as Kotlin, Swift or C++. Python through Kivy may not be able to reach native performance levels with heavy UI animations.

Rust (with Features, Pros, Cons)

Rust is a newer systems programming language that has gained a lot of attention. It delivers high performance similar to C, while offering strong memory-safety guarantees. Because of this, Rust is increasingly considered for mobile development, especially for building high-performance modules. Features: Rust compiles to native code and does not use a garbage collector. Its strict compile-time checks prevent issues like null pointer dereferences, data races, and other memory errors. Rust can compile to the ARM architectures used by Android and also supports iOS. This allows developers to write libraries or core logic in Rust and use them inside mobile apps.

• Pros: The largest positive of Rust is performance safety. It has similar performance to C/C++, with significantly reduced chances of memory leaks or crashes caused by stringent compiler tests. This renders Rust to be appealing to important mobile software parts where dependability is essential (e.g. crypto libraries, database engines or any element where a crash is not an option).
• Cons: The power of Rust is complex. It has a steep learning curve particularly because of its own ownership and borrowing regulations. Garbage-collected developers require time to adapt. This is able to retard development at the first stage. In the case of mobile app development, specifically, Rust does not have a well-established, popular framework to create a complete UI (there are experimental ones such as Dioxus or Tauri on mobile, but nothing as popular as Flutter/React Native).

Best Programming Language for PWAs

Progressive Web Apps are based on web technologies. In effect, in case you would like to construct a PWA, you would be dealing with web platform languages. The major languages (and combinations) to develop PWA include the following features, advantages, and disadvantages:

CSS/HTML/JavaScript (with Features, Pros, Cons)

The heart of any web application (including PWAs) is HTML, CSS and JavaScript. The structure, design, layout, and interactivity and logic are delivered through HTML, CSS, and JavaScript respectively. These three cannot be used interchangeably in their roles, but rather they are the building blocks of the web development.

• Pros: The biggest advantage is ubiquity. Any device with a web browser can run HTML, CSS, and JavaScript, making your app instantly cross-platform. Users don’t need to install anything, since PWAs load on demand. Development is also very accessible. Many beginners view HTML/CSS/JS as the best starting point because building a basic web app has a low barrier to entry. HTML and CSS are declarative and easy to learn, and JavaScript—while more complex—has extensive learning resources. Modern web standards have also added more native-like capabilities, such as offline storage, camera access, and push notifications. As a result, the gap between PWAs and native apps has narrowed.
• Cons: Web technologies still depend heavily on the browser. PWAs cannot match all native features. Deep integrations—such as accessing contacts or Bluetooth—may be unsupported or behave inconsistently across browsers. Performance can also be a concern. Although modern JavaScript engines are fast, heavy computations may still lag behind native code. PWAs rely on the browser’s rendering engine, so achieving perfectly smooth 60fps animations is harder compared to a well-optimized native app, even though CSS and canvas can come close.

TypeScript/JavaScript (Angular, React, Vue) (with Features, Pros, Cons)

Although you can build a PWA with plain JavaScript, using modern frameworks can make complex applications much easier to develop. TypeScript, a statically typed superset of JavaScript, is widely used in large web projects for better structure and maintainability. Frameworks and libraries like Angular, React, and Vue also help organize and streamline front-end development.

• Pros: TypeScript provides optional static typing to JavaScript, which helps to identify errors sooner and make large-scale projects easier to maintain. This may be essential because apps are becoming more popular, and many developers have discovered that it is the most suitable coding language to study to create apps on the web since it results in more robust codes. Actually, the usage of TypeScript has increased significantly (12 percent usage in 2017 and 35 percent in 2024 among developers). PWA TypeScript implies less runtime errors and more understandable interfaces between components. Concerning frameworks, they offer abstractions to handle UI and state in an efficient way.
• Cons: Frameworks may be too complicated. They have a learning curve and introducing TypeScript implies that developers have to learn typings and generics in addition to regular JS. Novices would feel overwhelmed to start right into an Angular or React application rather than a bare HTML/JS application. Frameworks also obfuscate part of the raw performance control; badly coded one-page applications are slow, resulting in large bundle sizes or slow initial load unless controlled (code splitting and tree shaking can mitigate this a lot).

PHP (with Features, Pros, Cons)

PHP is a server-side language commonly used to build web applications and back-end systems. So how does PHP relate to PWAs? A PWA still needs a back end to provide data, manage users, and process requests—unless it is completely static. Features: PHP runs on the server (for example, through Apache or Nginx with PHP-FPM) and outputs HTML or JSON that is sent to the client. It is a dynamically typed language embedded in HTML and powers many content management systems, including WordPress.

• Pros: PHP is decades old and is very widespread. By early 2025, approximately 74.5 percent of all known server-side-based websites use PHP. It implies that in the case when you are creating a web app (and therefore a PWA), PHP on the server is a time-tested, popular option. The APIs or web pages in PHP can be built in very efficient frameworks (Laravel, Symphony, etc.).
• Cons: PHP is not used for the client-side of PWAs – it has no role in the in-browser execution. So its relevance is limited to server operations. Some critics consider PHP to be an old or “uncool” technology now, with many modern startups preferring Node.js, Python, or Go for backends. While PHP’s core is solid, historically it had a reputation for inconsistent design (function names, etc.) and security pitfalls if code is not written carefully. The performance of raw PHP, while improved, can lag behind some newer languages for high-concurrency real-time applications. Additionally, PHP’s dominance is slowly eroding – it used to power ~79% of sites a few years ago and is now around 74%, indicating the rise of alternatives.

Ruby (with Features, Pros, Cons)

Ruby is another server-side language often used to build web applications through the Ruby on Rails framework. It is known for its clean syntax and focus on developer happiness. Like PHP, Ruby is typically used to build the back-end API or the web pages that a PWA relies on. Features: Ruby is a dynamic, pure object-oriented language. Its most popular framework, Rails, provides a full-stack platform with tools such as an ORM, routing, and built-in conventions that help speed up development.

• Pros: Ruby (particularly with Rails) can be used to develop web applications at a very fast pace. It has underpinned numerous successful applications (Twitter during its initial years, GitHub, Airbnb, Shopify – most of them began with Rails). The syntax of Ruby is expressive and brief and this can make the code easier to write and read. To create the backend of a PWA, Ruby on Rails can make an excellent option: this framework promotes the RESTful architecture and can be easily used to scaffold the resources that can be used by your front-end.
• Cons: The major weakness that has been mentioned about Ruby is performance. It is typically slower than compiled languages as well as slower than some interpreted counterparts on some tasks. Real-time applications with heavy traffic may not work with Ruby unless optimized or scaled with additional servers. There are examples of companies that began with Ruby, but after some time, they rewrote some performance-sensitive code in Java or Go.

FAQs About Choosing a Language for App Development

Choosing the best programming language for apps requires considering multiple factors. Below are answers to common questions that arise when deciding on a language for app development.

Which is the No. 1 Coding Language?

If we consider popularity across all kinds of development (not just apps), a few languages compete for the #1 spot. By most surveys in recent years, JavaScript is the #1 coding language in terms of usage. It has been the most commonly used programming language for over a decade. In the Stack Overflow Developer Survey 2023, for example, about 63.6% of developers reported using JavaScript – more than any other language. This makes sense given JavaScript’s omnipresence in web development (every web browser runs it), and its expansion to server-side (Node.js) and cross-platform apps.

However, another language has been rising fast: Python. Python started on Stack Overflow surveys as the 4th or 5th most used, but by 2023 it moved up to 3rd most commonly used, and some reports show that in specific domains Python even overtook others. According to GitHub’s Octoverse 2024 report, Python overtook JavaScript as the most active language on GitHub (measured by repository contributions), driven largely by its use in AI and data science. This was a significant shift after JavaScript’s long run at the top. Even so, JavaScript still maintains an enormous community and remains the most common for pushing code to repositories. On GitHub, if counting pure code pushes, JavaScript was still first, with TypeScript rapidly growing as well.

What Language is Most AI Coded In?

Artificial intelligence (AI) and machine learning (ML) have become huge in recent years, and one programming language stands out in this domain: Python. Python is widely regarded as the leading language for AI/ML coding. There are a few key reasons: it has very powerful libraries and frameworks for AI such as TensorFlow, PyTorch, scikit-learn, Keras, and many more. These frameworks, often written in low-level languages for performance (C/C++), provide Python interfaces, allowing developers to write AI code in Python with excellent efficiency. In a JetBrains 2024 developer ecosystem report, Python was explicitly noted as “the most commonly used programming language for AI and ML”. Its popularity in data science is immense – for example, in Kaggle surveys (Kaggle is a platform for data science competitions), usually over 80% of respondents use Python for their data science work, far above the next contender (which might be R or SQL for some tasks).

Python’s dominance in AI is also due to its simplicity – AI researchers and data scientists often are not from traditional software engineering backgrounds, so Python’s easy syntax allows them to be productive without dealing with low-level programming. It also integrates well with Jupyter notebooks, a key tool in the data science workflow.

That said, it’s worth noting that while Python is used to develop and prototype AI models, the underlying performance-critical code (like number crunching, tensor operations) is typically in C/C++ or optimized low-level implementations. Additionally, other languages have roles in AI: R is popular for statistics and data analysis, Julia has been emerging for numerical computing, and C++ is used when deploying AI in resource-constrained environments or for writing high-performance inference engines. 

Is Python or C++ Better For App Development?

Python and C++ serve very different purposes, and which is “better” depends on what aspect of app development we consider. Generally speaking, for mobile app development, C++ is rarely used to build the whole app, but it is used for parts of apps that need high performance, whereas Python is used scarcely for mobile UIs and more for backend or scripting tasks.

• Python is excellent for rapid development, easy syntax, and a huge range of libraries. If someone is making a simple app (perhaps a command-line tool, a quick web app, or a prototype), Python can be very productive. However, Python is interpreted and relatively slow, and on mobile it isn’t a native language (you’d need frameworks like Kivy or BeeWare, as discussed). Python is better suited for the server side of apps (like writing a web service the app talks to, or an automation script) rather than the app that runs on your phone natively.
• C++, on the other hand, is a powerful low-level language. It is compiled to native code and can achieve great performance. C++ is typically used in app development for performance-critical components or when interacting with low-level system APIs. For example, many games on mobile are built with C++ (using engines like Unreal, or cocos2d-x) because they need to maximize performance and want to share code with other platforms. Also, heavy-duty applications (like a complex image processing app, or AR applications) might use C++ for the core processing.

In summary, for mobile apps: C++ is used for performance-intensive tasks but not usually for the entire app, while Python is generally not used for the app’s GUI at all.

What Language Do Most Phone Apps Use?

Most smartphone apps today are built using a handful of primary languages, largely dictated by the platform:

• Android apps predominantly use Kotlin and Java. Kotlin has become the first-choice for many new Android apps since Google endorsed it. But a lot of existing apps and some new ones still use Java or a mix of Java/Kotlin.
• iOS apps primarily use Swift. Older apps or some maintained projects still use Objective-C, but Swift has overtaken it for new development. In 2024, it was reported that Swift accounts for about 65% of new iOS app projects, and an even higher proportion (87%) of new apps according to one mobile development report.
• Cross-platform apps (one codebase, multiple platforms) might use Dart (if built with Flutter), JavaScript/TypeScript (if built with React Native, Ionic, Cordova etc.), or C# (if built with Xamarin/MAUI). So if you consider those as phone apps too, a considerable number use these languages.

If one had to answer in simpler terms: Most Android apps use Java or Kotlin, and most iOS apps use Swift (with some using Objective-C). That covers the native sphere. Given the market share of Android and iOS, those are the prevailing languages in mobile. Cross-platform approaches are significant but still a subset.

Conclusion

In conclusion, the majority of phone apps use the platform-native languages: Kotlin/Java for Android and Swift/Objective-C for iOS. Cross-platform apps using languages like JavaScript, Dart, or C# also form a significant segment, but overall the native languages are most common in the app stores. Keep in mind the mobile app ecosystem is split between these two major platforms, so “most phone apps” essentially means “most Android apps and most iOS apps,” which we’ve addressed. Each aspiring app developer should choose the language according to the platform and approach that fits their goals – and thankfully, today’s options (Kotlin, Swift, Dart, etc.) are all modern, robust languages that make app development an exciting endeavor.

At Designveloper, we’ve spent the last decade helping global startups and enterprises bring their mobile app ideas to life using the best language for app development—tailored to each project’s platform, goals, and timeline. As a leading software development company in Vietnam, we’ve delivered over 150 mobile and web projects across industries like fintech, healthcare, logistics, and education.From building LuminPDF (used by over 50 million users) to launching custom apps for startups in the U.S., Singapore, and Europe, our team of 150+ experienced developers knows how to choose the right tools—whether it’s Kotlin for a high-performance Android app, Flutter for a unified codebase, or React and TypeScript for a blazing-fast PWA.