Reduce React Native APK Size by 70-80%: Complete Optimization Guide

Reducing the size of a React Native APK by 70-80% is achievable through a combination of code optimization, asset management, build configuration tweaks, and advanced tooling. This guide breaks down proven strategies to shrink your app’s footprint while maintaining top performance and functionality.

Why APK Size Matters?

Large APKs can lead to higher download abandonment, particularly in regions with slower internet or limited device storage. A smaller APK results in:

Better install rates
Improved user retention
Higher Google Play Store rankings

Let’s dive into key techniques for APK size reduction.

Optimize JavaScript and Native Code

Enable Hermes Engine

Hermes compiles JavaScript to bytecode, significantly reducing bundle size and improving startup time.

Android – in android/app/build.gradle:

project.ext.react = [ enableHermes: true ]

iOS – in Podfile:

use_react_native!(..., :hermes_enabled => true)

Hermes can reduce JavaScript bundle size by ~40%.

Remove Unused Libraries

Audit your package.json regularly.
Use tools like npm ls or yarn why <package> to identify unnecessary dependencies.
Replace bulky libraries with lighter alternatives:

Replace	With
`moment.js`	`date-fns` or `dayjs`
`lodash`	Native JS functions
Full `react-navigation`	Import only required navigators

Enable ProGuard or R8

These tools shrink and obfuscate Java/Kotlin code:

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

Expect native code size reduction of 15–20%.

Optimize Assets and Media

Compress and Convert Images

Use WebP instead of PNG or JPEG (25–30% smaller).
Compress images using TinyPNG or Squoosh.
Use vector icons (react-native-vector-icons) instead of bundling multiple static image files.

Load Assets Dynamically

Avoid bundling large media by loading assets from a CDN:

import FastImage from 'react-native-fast-image';

This reduces the initial APK size by loading content only when needed.

Remove Unused Fonts and Locales

Exclude fonts not used in your UI.
On iOS, restrict locales in Info.plist:

<key>CFBundleLocalizations</key>
<array>
  <string>en</string>
</array>

On Android, configure locales and screen densities in build.gradle:

defaultConfig {
  resConfigs "en", "xxhdpi"
}

Refine Build Configuration

Generate Android App Bundles (AAB)

AABs let Google Play deliver optimized APKs per device configuration.

In android/gradle.properties:

android.enableBuildCache=true
android.useAndroidX=true

Build the release AAB with:

./gradlew bundleRelease

Switching to AABs can reduce the APK size by 30–50%.

Split APKs by CPU Architecture

Exclude unnecessary architectures to reduce size:

android {
  splits {
    abi {
      enable true
      reset()
      include "arm64-v8a", "x86_64"
      universalApk false
    }
  }
}

Splitting by ABI can cut APK size by ~50%.

Advanced Optimization Techniques

Code Splitting and Lazy Loading

Load screens or components on demand:

const Settings = React.lazy(() => import('./Settings'));

This reduces the initial JavaScript bundle size.

Over-the-Air (OTA) Updates

Use CodePush to push updates without needing users to reinstall the app:

appcenter codepush release-react -a <app-name>

This keeps your APK minimal while delivering frequent updates.

Use Dynamic Feature Modules

Split features into downloadable modules:

// settings.gradle
include ':app', ':dynamic_feature'

Only necessary modules are downloaded, reducing install size.

Case Study: Reducing APK from 26MB to 3.1MB

Aglowid IT Solutions achieved a ~88% reduction by applying:

AABs with architecture splits
ProGuard and resource shrinking
WebP compression
Locale and font pruning

Final Checklist for APK Shrinking

Enable Hermes for bytecode compilation
Remove unused dependencies
Enable ProGuard/R8 and configure shrinking rules
Use compressed WebP images and vector icons
Generate AABs and split APKs by architecture
Implement code splitting and OTA updates
Audit assets, locales, and fonts monthly

Conclusion

By methodically applying these strategies, you can reduce your React Native APK size by 70–80%. Smaller APKs lead to higher install success, faster updates, and a better user experience. Continuous audits and adopting newer tools (e.g., React Native Reanimated 3) ensure long-term efficiency and performance.