10 Pro Tips to Reduce React Native App Size by 60%

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10 Pro Tips to Reduce React Native App Size by 60%

TL;DR:

Enable Hermes to reduce JavaScript bundle size by 15-25%.
Use Proguard for Android to optimize and shrink bytecode.
Optimize assets by compressing images and removing unused files.
Audit and remove unnecessary libraries to reduce app bloat.
Switch to Android App Bundles (.aab) for smaller, optimized downloads.

Introduction

In 2025, optimizing app performance and reducing install size are crucial to ensuring a seamless user experience. Whether you’re developing a productivity tool or a popular social platform, keeping your React Native app lightweight is key to improving user retention and boosting conversion rates. A large app size can lead to higher install friction, consume excessive device storage, and ultimately turn users away. As a leading React Native app development company, we know that developers are constantly searching for ways to reduce app size without compromising performance or features.

In this guide, we’ll walk you through the most effective strategies and tools to shrink your React Native app size by over 60%, making your app faster and more user-friendly.

1. Remove Unused Assets and Code

A common culprit of app bloat is unused images, fonts, and code.

Use tools like react-native-unused or depcheck to identify and remove dead files.
Audit your assets manually or use asset optimization tools.
Avoid bundling large sets of images you don’t need.

Reducing asset clutter can lead to a noticeable decrease in React Native app size.

2. Enable Proguard for Android

Proguard shrinks, optimizes, and obfuscates Java bytecode. It’s essential for trimming down your Android builds.

In android/app/build.gradle, configure:

release {
    minifyEnabled true
    shrinkResources true
    proguardFiles getDefaultProguardFile("proguard-android.txt"), "proguard-rules.pro"
}

Also, keep only necessary rules in proguard-rules.pro to avoid bloating the output.

This simple step can reduce React Native app size by 10-20% on Android.

3. Enable Hermes JavaScript Engine

Hermes is a lightweight JavaScript engine optimized for React Native.

To enable Hermes:

In android/app/build.gradle: hermesEnabled true
In ios/Podfile: Ensure Hermes is not commented out

Hermes dramatically reduces React Native app size by removing the need for JSC and optimizing runtime performance. Apps using Hermes often see a 15-25% decrease in bundle size.

4. Optimize Image Assets

Large image files can inflate app size unnecessarily. Compress and convert your assets:

Use react-native-image-resizer
Convert PNGs/JPEGs to WebP format
Tools like TinyPNG or ImageOptim are great for manual compression

This step alone can reduce React Native app size by several MBs.

5. Remove Heavy or Unused Libraries

Audit your package.json and dependencies:

Avoid UI kits like react-native-elements if you’re only using 10% of it
Replace bloated libraries with lightweight alternatives
Remove development tools like Reactotron from production builds

Every extra library adds to the final build, so trimming dependencies directly impacts your React Native app size.

6. Split APKs for Android

Instead of bundling everything into a single APK, generate multiple APKs for different architectures:

splits {
    abi {
        enable true
        reset()
        include 'armeabi-v7a', 'arm64-v8a'
        universalApk false
    }
}

This approach ensures that users only download what’s required for their device, helping reduce React Native app size.

7. Use Android App Bundles (.aab)

Switching from APK to AAB allows Google Play to serve optimized APKs tailored to device configurations.

Build with ./gradlew bundleRelease
Upload to Play Console for automatic device targeting

App Bundles can significantly reduce the size users actually download and install.

8. Enable Dead Code Elimination (DCE)

DCE removes unused code during bundling.

Update your metro.config.js:

transformer: {
  getTransformOptions: async () => ({
    transform: {
      experimentalImportSupport: false,
      inlineRequires: true,
    },
  }),
},

Inline requires help React Native defer module loading, resulting in reduced app size and faster startup.

9. Strip Debug Logs & Dev Tools

Debugging tools and logs inflate bundle size unnecessarily:

Use Babel plugins like babel-plugin-transform-remove-console to strip logs
Disable Flipper and Reactotron in production
Avoid loading debug assets in release builds

This helps streamline your production code and reduce React Native app size.

10. Use Code Splitting and Lazy Loading

Split large modules and screens into dynamically loaded components:

Use React.lazy() with Suspense or dynamic import()
Load maps, video players, or charts only when needed

While React Native doesn’t have full Webpack-like code splitting, lazy loading still offers a great way to reduce React Native app size.

Conclusion

In 2025, reducing React Native app size is no longer optional — it’s critical for staying competitive and retaining users. Whether it’s enabling Hermes or optimizing your asset pipeline, every small change contributes to a leaner, faster mobile experience. By applying these 10 strategies, you can achieve reductions well over 60%, making your app more efficient, installable, and user-friendly. If you’re looking for expert assistance, consider hiring React Native developers who can help you implement these optimizations and ensure your app performs at its best.

FAQs

Q1: How much can Hermes reduce my React Native app size?
Hermes typically reduces the JavaScript bundle size by 15-25% depending on the app.

Q2: What is the benefit of using .aab over APK?
App Bundles let Google Play deliver smaller, device-specific APKs, reducing download and install size.

Q3: Can I still use third-party libraries and reduce app size?
Yes, but only include the libraries you absolutely need. Audit your dependencies regularly.

Q4: Will Proguard affect my app performance?
No, it usually improves performance by removing unused code and optimizing bytecode.

Q5: Is there a risk in removing console logs automatically?
If done in production-only builds using Babel plugins, it’s safe and highly recommended to keep bundles clean.

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