The Great Divide: UI vs. Logic
The debate between Flutter and Kotlin Multiplatform (KMP) isn't just about programming languages; it's about architectural philosophy. One asks you to share your entire UI, while the other asks you to share only your business logic.
1. Flutter: The Speed of UI
Flutter's biggest advantage remains its unmatched development speed for UI-rich applications. With its own rendering engine (Canvas/Skia/Impeller), what you see on iOS is exactly what you get on Android. It's the perfect choice for teams that need high-fidelity brand consistency across platforms without maintaining multiple UI codebases.
2. KMP: The Native purist's Choice
Kotlin Multiplatform takes a different route. It doesn't touch the UI. Instead, it lets you share your core business logic—data layers, API clients, and computational models—while giving you 100% control over the native UI layer. This means your iOS app uses SwiftUI and your Android app uses Jetpack Compose.
3. Performance and Integration
While Flutter is fast, KMP is native. Because KMP compiles to native binaries for each platform, there's no runtime overhead. Furthermore, KMP integrates seamlessly into existing native codebases, making it the preferred choice for enterprise apps that are migrating gradually.
Conclusion
Choose Flutter if you want to ship a beautiful, UI-heavy app quickly with a single team. Choose KMP if you demand uncompromised native performance, want to leverage native UI capabilities, or need to share logic in a large, existing native ecosystem.
