Compress Images for Mobile Apps (Android & iOS Tips)
Published by ImageCompressor | Updated 2025
Introduction
Images are a core part of mobile UX, but they can also slow down your app, increase load times, and consume valuable storage. In this guide, we’ll cover how to properly compress and optimize images for mobile apps across Android and iOS platforms.
Why Image Compression Matters in Mobile
- Reduces app size and memory usage
- Speeds up launch time and in-app performance
- Improves load times for content fetched over network
- Reduces data usage for end users
Recommended Formats for Mobile
- WebP: Supported natively in Android and modern iOS. Great for quality and compression balance.
- HEIC: Apple’s preferred format. High quality, low file size.
- AVIF: Modern, ultra-efficient. Still gaining universal support but excellent results.
- SVG: For vector icons and illustrations.
Compression Methods
1. Offline Compression (Before Build)
- Use tools like ImageOptim, PNGGauntlet, Squash
- Export from Photoshop or Figma at optimized resolution
- Run through CLI tools:
jpegoptim,optipng,avifenc
2. Real-Time Compression (In-App)
- Android: Use
BitmapFactorywithinSampleSizeto downscale images - iOS: Use
UIImageJPEGRepresentationorUIImageHEICRepresentationfor compression
Responsive Image Delivery
Use multiple versions of assets to match screen density (mdpi, hdpi, xhdpi, xxhdpi, xxxhdpi) on Android, and @1x, @2x, @3x for iOS. Don’t serve oversized images when a smaller version will do.
Lazy Loading and Network Images
Load images on demand when they appear on screen. Use libraries like:
- Android: Glide, Picasso, Coil
- iOS: SDWebImage, Kingfisher
Best Practices
- Keep original asset dimensions close to display dimensions
- Use adaptive formats (WebP/HEIC/AVIF)
- Batch compress assets before adding them to the app
- Use image CDNs (Cloudinary, Imgix) for remote images
Conclusion
Optimizing image usage in mobile apps is essential for performance, size, and user experience. Choose modern formats, automate compression during your build, and use lazy-loading techniques to deliver images more efficiently across all devices.