React Native vs Kotlin: What Everything You Need To Know

Advantages of React Native

React Native delivers big-picture wins that make it a standout choice for developers. These pros focus on the real impact for your projects.

1. Write once and use it everywhere

One of the significant advantages it offers over Kotlin is that the same code can be shared across various platforms. This means eliminating the need for separate teams of developers for different platforms.

2. Faster Development Cycles

React Native cuts build times with its streamlined tools and workflows. Developers iterate quickly without complex native setups. This speed gets apps to market sooner.

3. Broader Talent Pool

JavaScript skills open React Native to a wide range of coders. Web developers can jump in without learning deep native systems. It’s a practical perk for hiring and scaling teams.

4. Community-Driven Solutions

When it comes to choosing a language for any kind of tech development, we can’t ignore the benefits of the developer community. The community acts as a support system. So, when you are stuck, you can seek assistance from other developers across the globe.

Disadvantages of React Native

Even with its strengths, React Native has its downsides for developers to consider. These cons highlight real-world challenges.

1. Performance is lower than native apps

React native apps are impressively fast, but still, native apps are faster in terms of performance. React Native apps comprise a bridge called “React Native bridge” between the UI thread and the JavaScript function as a bottleneck.

2. Upgrading can be painful sometimes

Upgrading from one version to the latest version can be a tedious task. Even a small mistake can cause a delay in upgrading to the latest version, providing users with plenty of new features and tools to improve application performance.

3. Lack of custom modules

Since it appears to be a perfect language for Native app development with a great number of modules to build a variety of components, it still lacks some custom modules, and you might be forced to create components from scratch.

Advantages of Kotlin

Kotlin brings strategic benefits that solidify its role in Android development. These pros emphasize its value beyond the code.

1. Reduced Development Overhead

As compared to Java, Kotlin syntax is more concise, reducing the significant amount of boilerplate code needed to declare variables, classes, and methods.

2. Official Android Support

Google strongly recommends using Kotlin for Android development; many new APIs, such as Android FTX, JetPack compose, etc., are built around Kotlin.

3. Modern App Building

It is a functional programming language that features modularity and reusability, concurrency and parallelism, concise coding, etc., making it a great choice for modern app development.

Disadvantages of Kotlin

Kotlin’s gains come with some limitations that can’t be ignored. These cons point out its practical drawbacks.

1. It is still a young language

While Kotlin has gained significant popularity and adoption in recent years, it is still a relatively new programming language compared to others, like Java. As a result, the resources and community of developers available to support and assist with Kotlin development may be more limited compared to other languages. This can sometimes make it challenging for developers to get help or find answers when facing problems or challenges during app development with Kotlin.

2. A bit slower than Java

Even though it is considered an enhanced version of Java, it is comparatively slower than Java in terms of the speed of applications in the Android ecosystem.

3. Resources are limited

Though it has been reaching a new height with the passing years, it has yet to achieve the milestone of a list of matured programming languages. So, when you are in trouble with your app, you may find it difficult to get assistance from the developers’ community as they are limited in number.

System Requirements for Kotlin React Native Development

Building apps with Kotlin React Native demands specific setups. Here’s what developers need to get started with each.

React Native

1. Runs on Windows, macOS, or Linux with Node.js (v16+ recommended) and npm/yarn installed.

2. Requires Android Studio for Android development or Xcode (macOS only) for iOS, plus an emulator or physical device.

3. Needs 8GB RAM minimum, though 16GB is ideal for smooth performance with emulators.

Kotlin

1. Works on Windows, macOS, or Linux with Android Studio (latest stable version) as the primary IDE.

2. Requires JDK 11+ for compilation and an Android emulator or device for testing.

3. Demands at least 8GB RAM, with 12GB+ recommended for faster builds on complex projects.

Best Use Cases for React Native vs Kotlin

React Native and Kotlin excel in different scenarios. These use cases show where each thrives for developers.

React Native

1. Ideal for startups needing quick MVP launches across iOS and Android with one codebase.

2. Suits apps with moderate UI needs, like social media (e.g., Instagram) or e-commerce platforms.

3. Best for teams leveraging JavaScript skills to iterate fast on dynamic content apps.

Kotlin

1. Perfect for Android-first apps requiring deep native integration, like banking or fitness trackers.

2. Fits large-scale projects needing robust performance, such as enterprise tools (e.g., Trello).

3. Great for developers building with Jetpack Compose or maintaining Java-based codebases.

Market Analysis: Developer Adoption of React Native and Kotlin

React Native and Kotlin have carved distinct paths in the dev world by 2025. Here’s how adoption trends stack up.

React Native

1. Holds strong with 35% of developers using it for cross-platform work, per 2024 surveys, thanks to its JavaScript base.

2. Adoption thrives among startups and web-centric teams, with giants like Facebook and Airbnb boosting its cred.

3. Growth has slowed slightly as Flutter gains ground, but its mature ecosystem keeps it a top pick.

Kotlin

1. Used by 60% of Android developers, up from 40% in 2020, fueled by Google’s push and Jetpack Compose adoption.

2. Multiplatform use (KMP) is rising, with 15% of devs experimenting cross-platform, seen in apps like Netflix.

3. Strong in Android-first markets, though its smaller community limits broader uptake compared to React Native.

Performance Benchmark

Performance matters in mobile apps—users expect fast load times, smooth interactions, and efficient resource use. So, how do these two compare? Let’s explore the benchmarks.

1. Startup Time

Startup time measures how quickly an app launches and becomes usable. This is often the user’s first impression of an app.

Kotlin:

Native Android apps built with Kotlin typically have faster startup times. Since the code compiles directly to bytecode for the Android runtime, there’s no additional overhead. The app initializes using the platform’s optimized pathways, resulting in snappy launches.

React Native:

React Native apps require the JavaScript engine to boot up and establish a bridge between the JavaScript thread and native components. This introduces a slight delay, especially noticeable in complex apps with heavy initialization logic. For simpler apps, the gap is minimal, but it widens as complexity grows.

Verdict: Kotlin wins here. Native execution skips the runtime overhead that React Native incurs.

2. Memory Usage

Memory efficiency is critical on mobile devices, where resources are constrained.

Kotlin:

Native apps use memory more efficiently because they tap directly into Android’s memory management system. There’s no need for extra layers, keeping memory footprints lean.

React Native:

React Native juggles memory for the JavaScript runtime, the bridge, and native modules. This multi-layered approach increases memory usage. For example, a developer once reported reducing idle memory usage by 21 times after rewriting a React Native app in Kotlin—an extreme but telling case.

Verdict: Kotlin takes the lead. React Native’s additional runtime layers inflate memory demands, though optimizations like lazy loading can help mitigate this.

3. CPU Usage

CPU usage affects battery life and app responsiveness, especially during intensive tasks.

Kotlin:

As a statically typed, compiled language, Kotlin runs natively on Android, minimizing CPU overhead. It directly accesses device capabilities without intermediaries, making it efficient for heavy computations.

React Native:

React Native runs JavaScript in a separate thread, communicating with native code via a bridge. This bridge can become a bottleneck, increasing CPU usage during complex operations. For lightweight apps, the difference is subtle, but it scales with app intensity.

Verdict: Kotlin is more CPU-efficient. React Native’s threading and bridge introduce overhead that native execution avoids.

4. Frame Rates and Animation Smoothness

Smooth animations are essential for a polished user experience, typically measured in frames per second (FPS).

Kotlin:

Native Android apps handle animations via the platform’s optimized rendering pipelines, ensuring high frame rates and fluid interactions. The direct access to hardware keeps animations smooth, even under load.

React Native:

Historically, React Native animations run on the JavaScript thread. If that thread gets bogged down, frames drop, leading to jank. However, tools like Reanimated v3 shift animation logic to the native side, closing the gap. Still, out-of-the-box animations in React Native lag behind native performance.

Verdict: Kotlin excels for smooth animations. React Native has improved, but native rendering remains superior for consistent FPS.

5. App Size

App size impacts download times and storage usage—key concerns for users.

Kotlin:

Native Kotlin apps are compact, bundling only the compiled code and necessary resources. No extra runtimes or libraries are required.

React Native:

React Native apps include the JavaScript runtime and dependencies, inflating their size. One developer noted an 11.5x size reduction after switching to Kotlin. Techniques like code splitting and tree shaking can trim React Native apps, but they still tend to be larger.

Verdict: Kotlin produces smaller apps. React Native’s cross-platform benefits come at the cost of a heftier package.

Which one is better? React Native or Kotlin?

It’s tough deciding between React Native and Kotlin when you’re looking to develop a mobile app that functions well on both iOS and Android. These platforms have been leading the pack for mobile apps, and for good reason. They’re high-quality, responsive, and reliable, so you can get the results you need. However, they’re also quite different, so deciding which is better for your project can be tricky.

When choosing between React Native and Kotlin, think about what your project needs. React Native is a great choice if you're planning to release apps quickly. It's a good way to write apps that can work on both iOS and Android. It also makes it easy to update your apps often.

Kotlin is a better option if you're writing an app that's specifically for Android. You might think that React Native is the better option. After all, it has a solid library, it's easy to use, and it has a lot of flexibility, but it does fall behind in terms of performance. If you want the best performance, Kotlin is the way to go.

When deciding what to use for making Android apps, whether it’s React Native or Kotlin, here is some guidance to help you make the right choice. If your app is fairly basic in functionality and design, then React Native can work well. But Kotlin is probably better for more complex Android apps. Lower-powered Android devices may experience better performance with React Native than with Kotlin or other frameworks, but Kotlin is probably the way to go for complex Android apps since it allows for more design options and layouts, plus native API access. Kotlin is faster than React Native, so if your app has a lot of background tasks to perform, Kotlin may be the best choice. Advanced or high-performance Android apps are a natural fit for Kotlin because of its native features.

React Native vs Kotlin: Summing up

In this article, we have walked through both React Native and Kotlin. Both languages are very popular for cross-platform app development, and both are supported by big, established names in the market. React Native, in particular, is a well-established tech stack that is supported by Facebook and a strong community of developers.

On the other hand, Kotlin is prominently used in Android app development and has strong support from Google. Also, it has gained traction in multiplatform app development as there are very valid and good reasons to go with Kotlin, not to mention that it is powerful and is able to utilize native components.

To summarise, the tech stack for your mobile app development may be finalized after your needs are clear.

Have you decided on the cross-platform stack for your next project?

What is your requirement?

Do you want a native app or a hybrid app for your business?

Feel free to contact us for more information. Brilworks is top-rated React native development agency with an experienced team of React native developers that offers both hybrid and native app solutions at affordable cost and round-the-clock support.