How to Successfully Migrate from Native Apps to Flutter

There’s a quiet shift underway in the mobile development world. For years, native app development was the gold standard—built separately for iOS and Android to get the best performance and feel. But over time, that approach started to show its cracks.

Maintaining two codebases means twice the effort: separate teams, duplicated features, and often misaligned release schedules. Add to that the rising cost of development and growing pressure to iterate faster, and it’s easy to see why businesses are rethinking their tech stack.

That’s where Flutter comes in. Google’s cross-platform framework has gone from niche experiment to mainstream powerhouse. In fact, according to Statista, Flutter was the most popular cross-platform mobile framework in 2023, used by 46% of developers—beating out React Native and far outpacing traditional native stacks. What’s drawing teams in? The ability to write once and ship everywhere, without sacrificing the quality users expect from native apps.

And this isn’t just a startup trend. Companies like Toyota, eBay, and ByteDance have adopted Flutter for apps that serve millions of users. Whether you’re launching an MVP or replatforming an enterprise product, Flutter offers a way out of the fragmented, high-cost world of native development—and that’s a big reason why so many are making the switch.

What Are the Key Differences Between Flutter and Native Development?

Before comparing the two approaches, it helps to understand what each actually is.

What is Native App Development?

Native app development refers to building mobile apps using the programming languages and tools officially supported by the platform. For iOS, that means Swift or Objective-C. For Android, it’s Kotlin or Java. These apps are compiled directly for the device, which gives them excellent performance and deep access to native APIs, sensors, and UI components.

The upside? You get full control over platform-specific behavior. The downside? You’ll need to build and maintain two separate codebases if you want your app on both iOS and Android—often with two different teams and tech stacks.

What is Flutter?

Flutter is a modern, open-source framework developed by Google for building cross-platform applications using a single codebase. It uses the Dart language and comes with its own rendering engine (Skia), allowing developers to craft custom UIs that look and behave consistently across platforms.

Instead of relying on native UI elements, Flutter draws everything from scratch—giving you pixel-level control. And because it compiles to native ARM code, performance is often on par with native apps.

Flutter vs Native: What Really Sets Them Apart?

At first glance, Flutter vs native development might seem like two very different worlds. But when you break it down, the real difference lies in how much control and efficiency you want in your development process.

Native apps offer that deep, device-level integration and platform-specific UI fidelity. But with it comes duplication—two codebases, more testing, and increased chances of mismatch between iOS and Android releases.

Flutter flips this equation. It uses a single Dart codebase to target both platforms. That means one team, one design system, and unified development cycles. For product teams under pressure to ship quickly without compromising on UI or performance, that’s a game-changer.

Another key native vs flutter difference lies in rendering. Native apps use built-in UI components, while Flutter uses its own engine to draw the UI. This lets you create consistent, custom interfaces that look the same everywhere—without worrying about platform limitations.

Ultimately, Flutter vs Native isn’t about right vs wrong—it’s about what you value more: platform depth or development agility. For many teams, especially those working across multiple devices, Flutter is quickly becoming the default.

How Does Flutter Perform Compared to Native Apps?

Performance is usually the first question that comes up when teams consider migrating from native to Flutter. Native apps have long been the gold standard for speed and responsiveness, especially when it comes to graphics-heavy or hardware-dependent features. But Flutter has come a long way—and for most use cases, it delivers a performance level that’s hard to tell apart from native.

So how does Flutter performance really stack up?

Flutter compiles to native code

Flutter apps are compiled to native ARM machine code using Dart’s ahead-of-time (AOT) compilation. This means the final app doesn’t run in a web view or rely on a bridge layer—it runs directly on the device. As a result, most UI interactions, animations, and transitions feel fluid, with frame rates reaching 60fps or 120fps on high-refresh-rate screens. In practical terms, this means Flutter apps launch fast, respond quickly to input, and don’t feel sluggish. Flutter vs native performance is at par if not better than either thanks to the compilation approach. 

Real-world performance is nearly identical

In typical business or consumer apps—like e-commerce, social feeds, productivity tools, or media apps—Flutter performs almost identically to native apps. A performance study by inVerita found that Flutter’s UI rendering, navigation, and startup time were “almost indistinguishable” from native benchmarks. Unless you're building something that pushes the hardware to its limits, users are unlikely to notice any difference.

Flutter Supports Native Integrations

Flutter is built to work alongside native code when needed. For apps that require access to low-level platform features—like real-time sensor data, AR/VR frameworks, or advanced GPU rendering—Flutter provides a powerful mechanism called platform channels. This allows developers to invoke native Swift, Kotlin, or Java code directly from Dart, seamlessly extending Flutter apps with native functionality.

Consistency is Flutter’s hidden strength

One of Flutter’s biggest performance advantages isn’t about speed—it’s about predictability. With native development, differences in platform behavior can create inconsistencies in layout, animation, and rendering. Flutter avoids this by using its own rendering engine (Impeller) to draw every pixel identically across iOS and Android, which results in a smoother and more uniform experience for users—and fewer performance issues for developers to troubleshoot.

When Does It Make Sense to Migrate Your Native App to Flutter?

Not every app is built to last forever on its original tech stack. Business needs change, design standards evolve, and teams often outgrow the limitations of maintaining separate native codebases. That's where Flutter enters the conversation—not as a trend, but as a strategic option for companies looking to simplify, scale, and speed up their development process.

But timing the migration right is critical. So when exactly does it make sense to move from native to Flutter?

When you're maintaining two separate codebases

If you're managing iOS and Android apps separately, you’re likely facing slower development cycles, duplicated QA effort, and inconsistent UI across platforms. Flutter eliminates these silos by offering a single codebase that works across both platforms, significantly reducing team overhead and long-term technical debt.

During a major redesign or app overhaul

If your app is due for a full refresh—whether it's visual design, performance optimization, or a structural revamp—this is an ideal time to consider migrating. Instead of pouring resources into two native rebuilds, switching to Flutter allows you to consolidate and modernize in one go, while positioning your product for long-term scalability.

When expanding to web, desktop, or new platforms

Native development doesn’t scale well when your product roadmap expands beyond mobile. If you're now targeting web, desktop, or even embedded systems, Flutter gives you a head start. Its cross-platform capabilities mean you can launch new experiences faster without starting from scratch for each device. So, Flutter vs native app development should undergo the test of expansion and ease of scale, to determine how well flutter does on this benchmark. 

When native-specific dependencies are minimal

Flutter can handle platform-specific code through plugins and platform channels, but if your current native app heavily relies on low-level SDKs or deep hardware integrations, migration becomes more complex. In such cases, a hybrid or gradual migration strategy—where you transition only parts of your app—may be more practical.

When you're building content-rich or multi-feature apps

Apps with rich UI layers, dynamic content, or frequent updates—like e-commerce platforms, productivity tools, and customer portals—tend to benefit the most from migration. These apps don’t depend heavily on native hardware, and the unified Flutter stack makes it easier to maintain and scale over time.

What Are the Challenges in Migrating Native Apps to Flutter?

Migrating to Flutter isn’t just a copy-paste job—it’s a rethink of how your app is structured, how your teams work, and how platform-specific functionality is handled. While the benefits of switching to Flutter are clear, there are a few challenges that product teams need to be aware of before diving in.

Understanding these upfront can help avoid surprises and shape a smoother migration roadmap.

You can’t reuse most of your native code

One of the first hurdles is that your existing Swift, Kotlin, or Java code won’t carry over directly into Flutter. Since Flutter uses Dart and its own UI framework, everything from layout to navigation logic needs to be rewritten. While some backend integration code or business logic can be reused if it’s modular and platform-agnostic, most of your UI layer will need to be built from scratch.

Handling native SDKs and platform channels

If your current app relies on native SDKs—for things like payments, background services, media processing, or Bluetooth—you’ll need to connect those through platform channels in Flutter. While this is entirely possible and well-documented, it adds complexity and sometimes requires writing native code alongside your Dart code. Teams without strong native experience may find this step requires additional support.

Managing third-party plugin compatibility

The Flutter ecosystem is strong, but it’s still catching up in certain areas compared to native ecosystems. While many common SDKs have Flutter equivalents or wrappers, not all third-party tools support Flutter out of the box. You may need to build or adapt plugins manually, especially for niche SDKs or region-specific tools.

Team ramp-up and tooling shift

Switching to Flutter also means investing in Dart fluency and adjusting your dev workflow. Your team will need to get familiar with Flutter DevTools, hot reload, widget trees, and Flutter’s rendering model. While these tools are intuitive once adopted, there is a learning curve—particularly for teams used to Xcode, Android Studio, or platform-specific testing frameworks.

Integration testing and QA setup

Testing strategies also need rethinking. Native apps often use platform-specific UI testing tools, while Flutter offers its own testing stack—widget tests, integration tests, and golden file testing. Teams need to rebuild their QA automation setups and adjust how they measure coverage and performance, especially during the transition period.

The Flutternest Playbook: Step-by-Step Migration from Native to Flutter

Migrating a native app to Flutter is not just a tech shift—it’s a product decision. At Flutternest, we treat migration as a balance between engineering reality and business goals. We’ve refined a process that works across startup MVPs, high-scale SaaS platforms, and legacy enterprise apps alike.

Here’s how we do it—step by step.

1. Assess the Native App’s Architecture and Roadmap

The first step in any migration is understanding what you’re working with. We begin by performing a thorough audit of the existing iOS and Android codebases—not just looking at what they do, but how they’re structured.

We assess:

• Which modules are business-critical vs. legacy

• Where duplicate logic or redundant screens exist across platforms

• What backend services and APIs the app relies o

• Which parts of the app are deeply tied to native SDKs or hardware integrations (e.g., camera, sensors, biometrics)
  
  

This is also the point where we align with your product roadmap. If you’re planning a redesign, launching in new markets, or rolling out major new features, the timing for migration might be ideal. Often, we recommend migration as part of a roadmap pivot—turning tech debt cleanup into an opportunity to modernize.

2. Decide the Migration Strategy: Full vs. Phased

There’s no universal answer to "should we rewrite the whole thing?” So we help you make that call with tradeoffs clearly mapped.

For smaller, simpler apps—especially MVPs or internal tools—a complete rebuild in Flutter is often more efficient. It allows you to streamline the codebase, standardize the UI, and move fast without the constraints of legacy native patterns.

For larger apps with active users and multiple feature sets, we often recommend a phased migration strategy:

• We start by identifying low-risk modules (like onboarding flows, settings, or dashboards).

• These are rebuilt in Flutter and embedded into the native app.

• Gradually, more complex modules are transitioned over.
  
  

This modular path helps preserve business continuity, avoid regression issues, and get internal teams comfortable with Flutter workflows—all while proving Flutter’s value in production.

3. Set Up Flutter Within the Native App (Hybrid Approach)

Flutter doesn’t force an all-or-nothing approach. We leverage this flexibility by embedding Flutter modules inside the existing native shell. This lets us ship new Flutter-based features while still relying on native code where it’s stable or tightly coupled to device-specific functionality.

This hybrid setup is perfect for:

• Teams on tight deadlines who want to modernize incrementally

• Apps that can't afford downtime during migration

• Experimenting with Flutter in production without committing to a full rewrite upfront

  
  

We handle all inter-module communication via platform channels and isolate dependencies cleanly so that Flutter modules can scale independently over time.

4. Rebuild UI Using Flutter’s Widget System

UI migration is more than a visual translation. It’s an opportunity to clean up inconsistencies, unify design systems, and introduce components that scale better across devices.

We rebuild each screen in Flutter using:

• Flutter’s rich widget tree to handle responsive layouts

• Custom reusable components for speed and scalability

• Native-like gesture handling and animations, rendered using Flutter’s Skia engine
  
  

This process is not about copying your current UI pixel for pixel—it’s about rethinking it in a way that delivers a consistent, elegant experience across iOS and Android, with less overhead in the future.

5. Reuse Existing APIs and Backend Integrations

One of the biggest wins in a migration project is retaining your backend layer. We integrate Flutter with your existing:

• RESTful or GraphQL APIs

• Auth systems (OAuth2, Firebase Auth, social logins)

• Analytics (Mixpanel, Firebase, Segment)

• Third-party services (payments, chat, etc.)
  
  

Flutternest takes a service-oriented view here—treating the backend as a stable foundation, while the Flutter frontend becomes a faster, more scalable presentation layer. This helps reduce risk and speed up delivery cycles.

6. Bridge Native Code Where Needed

For functionality that still depends on native OS-level APIs—like push notifications, background tasks, biometric auth, or platform-specific SDKs—we write lightweight bridges using Flutter’s platform channels.

We maintain small, clean Kotlin/Swift wrappers for native features and expose them to Dart code in a controlled, testable way. Our aim is to:

• Keep the Flutter codebase clean and maintainable

• Avoid overcomplicating platform channels unless truly necessary

• Lean on community-supported plugins when available, and extend them when not
  
  

This keeps the app’s architecture clean while preserving all critical native functionality.

7. Test, Benchmark, and Launch Gradually

Migration isn’t just about rewriting—it’s about validating. We bake in test coverage from day one:

• Widget tests for UI behavior

• Integration tests across major flows

• Performance profiling to compare Flutter vs. native baseline

• Regression monitoring through Firebase or Sentry
  
  

Before rolling out, we recommend A/B testing or staged releases (via Firebase Remote Config or app store phased rollout). This lets you track performance metrics, crash rates, and user behavior in production—ensuring that the Flutter-based experience doesn’t just match native, but surpasses it.

Real-World Migration Examples: Who’s Done It and Why?

You’re not the first to ask, “Is migrating from native to Flutter worth it?” Fortunately, we don’t need to rely on theory alone. Over the last few years, some of the world’s most respected tech companies have made the leap—and their results say a lot about what Flutter can do at scale.

Google Pay: From Native to Flutter, Globally

One of the most high-profile migrations was Google Pay’s transition to Flutter. Initially built using native stacks, Google’s team rewrote the app in Flutter to unify their development process across markets. The result? A 35% reduction in lines of code, a faster release cycle across both Android and iOS, and improved developer efficiency across multiple global teams. The app still integrates complex native features like NFC and banking SDKs—but Flutter powers the majority of its UI and logic.

BMW: Performance + UI at Enterprise Scale

BMW re-architected its entire in-car mobile experience using Flutter, serving millions of users through their “My BMW” app. They needed a framework that supported real-time updates, native-like performance, and a consistent UI across screen sizes and operating systems. Flutter delivered—and their engineering team publicly credits Flutter for faster updates and reduced maintenance complexity across their global app ecosystem.

Nubank: Latin America’s Leading Fintech

Nubank, one of the largest digital banks in the world, migrated from native to Flutter to streamline its development efforts across iOS and Android. As a fintech platform, performance and security were non-negotiable. Flutter allowed them to roll out features faster, keep visual consistency across devices, and reduce context switching for developers. Today, Nubank maintains its core app in Flutter and actively contributes to the open-source ecosystem.

Reflecting Flutternest’s Own Work: Rebuilding a Native B2C Ecommerce App in Flutter

One of our clients—a growing B2C ecommerce platform—approached us with a problem many startups face at scale. They had two fully built native apps, one for iOS and one for Android, developed by different vendors over time. The user experience was inconsistent across platforms. Features launched on Android took weeks to reach iOS. Maintaining both codebases required two separate teams and double the testing effort.

More critically, their roadmap included launching a web app version and expanding to new geographies. But with the current setup, they were already stretched thin.

Our approach began with an audit of their native app architecture. We identified that about 70% of their functionality—catalog browsing, user onboarding, cart logic, checkout flow—was duplicated across platforms. However, features like payments and push notifications were tightly coupled to native SDKs.

Rather than rewriting everything from scratch, we designed a phased migration strategy:

• First, we rebuilt the entire onboarding, login, and catalog experience in Flutter.

• We embedded this Flutter module inside both native shells to test live performance with real users.

• Over the next sprint cycles, we added cart and checkout flows, reused the backend APIs, and bridged native code for payments and notifications using platform channels.

• We used Firebase Remote Config to toggle features and staged the rollout to 10%, then 50%, then 100% of users.
  
  
  

The results within 3 months:

• 40% reduction in crash reports and UI-related bugs

• Feature parity across platforms achieved for the first time

• 2x faster iteration cycle for new feature releases

• Plans now in place to sunset native code and unify all mobile and upcoming web features in Flutter
  
  

This project became a model we now use often: start with UI-heavy flows, keep backend untouched, and layer native functionality back in where needed. It’s fast, controlled, and lets product teams unlock Flutter’s benefits early without business risk.

Conclusion: Should You Choose Flutter or Native for the Future?

For years, native app development was the default for serious products. It made sense—maximum control, top-tier performance, and deep access to platform features. But the landscape has changed.

Today, building and maintaining separate apps for iOS and Android isn’t just resource-intensive—it slows down innovation. For companies chasing tighter release cycles, cleaner UI consistency, and platform reach beyond just mobile, the native approach is starting to feel like a limitation.

Flutter offers a clear path forward. It’s not just about writing once and running everywhere—it’s about doing more with less. One codebase. One design system. One development team. Whether you're launching an MVP or modernizing a legacy system, Flutter delivers speed, performance, and maintainability without the typical tradeoffs of cross-platform tools.

That said, there will always be edge cases where native still makes sense—especially for apps that lean heavily on device hardware, OS-level background services, or ultra-low-latency rendering. But for the vast majority of business apps, customer-facing platforms, and internal tools, Flutter isn’t just a viable alternative—it’s a strategic advantage.

At Flutternest, we’ve seen it firsthand: startups go live faster, enterprises regain control over their release cycles, and product teams finally break out of the native-vs-native trap. Migrating to Flutter isn’t just about changing code. It’s about changing what’s possible.

Frequently Asked Questions (FAQs)

Is Flutter better than native app development?

Flutter is better than native in many cases—especially when time to market, cross-platform consistency, and development cost are priorities. With a single codebase, Flutter allows teams to build for both iOS and Android faster. Native may still have an edge in performance for highly hardware-dependent or OS-integrated applications, but for most business use cases, Flutter performs comparably and delivers faster.

How hard is it to migrate from native to Flutter?

The difficulty of migration depends on your app’s complexity and dependencies. If your app has a lot of custom UI or shared logic, Flutter makes migration easier. However, apps with deep native SDKs or low-level platform code may require custom platform channels and staged migration. At Flutternest, we typically follow a phased migration strategy to reduce risk and accelerate delivery.

Will I lose native performance if I switch to Flutter?

In most scenarios, no. Flutter compiles to native ARM code and uses GPU rendering to deliver high-performance UIs. For everyday business apps, social platforms, ecommerce flows, and productivity tools, users won’t notice a difference. That said, for niche apps requiring extreme performance or advanced hardware access, native still holds a slight lead.

Can Flutter completely replace native development?

For most projects—yes. Flutter can cover nearly all functionality required in modern mobile apps. It supports camera access, geolocation, push notifications, payments, and much more through its growing plugin ecosystem. Native development is only essential when you need deep OS-level control, custom device drivers, or features not yet accessible via Flutter plugins.

How long does it take to migrate a native app to Flutter?

Timelines vary depending on the size and structure of your existing app. A small native app can often be migrated in 4–6 weeks. Mid-sized apps typically take 8–12 weeks using a phased rollout. At Flutternest, we prioritize high-impact modules first—like onboarding, dashboard, or content display—and then migrate core flows progressively to ensure stability and speed.