Kotlin Multiplatform vs Flutter: Which Cross-Platform Framework Should You Choose in 2025?

Choosing the right cross-platform development framework can be challenging. Two of the most popular options in 2025 are Kotlin Multiplatform (KMP) and Flutter. In this article, we’ll compare Kotlin Multiplatform vs Flutter across performance, code sharing, UI development, and more to help you make the best decision for your next mobile or multi-platform project.

What is Kotlin Multiplatform?

Kotlin Multiplatform (KMP) is a framework developed by JetBrains that allows developers to share code across platforms such as Android, iOS, desktop, and web. It focuses on sharing business logic while letting developers build native UIs for each platform using tools like Jetpack Compose for Android and SwiftUI for iOS.

Key Features of KMP:

  • Share business logic and data layers across platforms
  • Write platform-specific UIs using native tools
  • Fully integrates with existing native codebases
  • Backed by JetBrains and uses the Kotlin language

What is Flutter?

Flutter is Google’s open-source UI toolkit for building natively compiled applications from a single codebase. It supports Android, iOS, web, desktop, and embedded systems using the Dart programming language.

Key Features of Flutter:

  • Write once, deploy everywhere: UI and logic in a single codebase
  • Custom rendering engine (Skia)
  • Rich set of pre-built widgets
  • Fast development with hot reload

Read Also: Shorebird Library: Supercharge App Distribution with Flutter

Kotlin Multiplatform vs Flutter: Feature Comparison

1. Code Sharing

FeatureKotlin MultiplatformFlutter
UI Code Sharing❌ Native per platform✅ Fully shared UI code
Business Logic✅ Shared across platforms✅ Shared across platforms
Platform Integration✅ Native interoperability⚠️ Requires platform channels

Verdict: If you want to share only business logic and keep native UIs, choose KMP. For full codebase sharing, Flutter wins.

2. UI and UX

  • KMP provides 100% native UI, meaning your app will feel exactly like it was made for the platform.
  • Flutter offers a consistent look and feel across platforms but may deviate slightly from native behaviors.

Verdict: For native feel and experience, KMP is better. For custom UIs and fast design, Flutter shines.

3. Performance

  • KMP runs natively, as it uses the platform’s own UI and compiled Kotlin code.
  • Flutter is performant but uses its own rendering engine which may add slight overhead.

Verdict: KMP offers closer-to-the-metal native performance, especially for UI-heavy or graphics-intensive apps.

4. Development Experience

FeatureKotlin MultiplatformFlutter
LanguageKotlinDart
Hot Reload❌ No✅ Yes
ToolingAndroid Studio, IntelliJ IDEAAndroid Studio, VS Code
Learning CurveMedium (if familiar with Kotlin)Low–medium (with Dart)

Verdict: Flutter provides a faster feedback loop with hot reload and better tooling for UI.

5. Community & Ecosystem

  • Flutter has a larger community, more packages, and extensive documentation.
  • KMP is growing rapidly, especially among Kotlin/Android developers, but is less mature.

Tip: Check out the official Flutter packages or JetBrains KMP docs for support.

When to Choose Kotlin Multiplatform

Choose KMP if:

  • You want native UI on each platform
  • You are building on top of existing native apps
  • You prefer Kotlin and are already using Jetpack Compose or SwiftUI

When to Choose Flutter

Choose Flutter if:

  • You need to build and ship apps quickly across multiple platforms
  • You want a unified UI codebase
  • You’re developing a new project with a custom look and feel

Read Also: Optimizing Flutter App Performance: Avoid Excessive Use of Opacity and Clipping

Final Thoughts

The decision between Kotlin Multiplatform vs Flutter comes down to your project needs. KMP is ideal for teams that want to share business logic while retaining platform-native UI and performance. Flutter is perfect for those who value speed, unified development, and custom UIs. Both are powerful, modern tools for cross-platform development—your use case will determine the best fit.

LOGIQUE is a company that provides application development services using various technologies, including Flutter. With a team of experienced developers, we are ready to help design and develop high-quality applications that are responsive, scalable, and tailored to the business needs in Indonesia. Want to learn more about the services we offer? Contact the LOGIQUE team today!