Flutter Migration
Your app, rewritten in Flutter. And with AI where it never had any.
React Native · Swift/Kotlin · Ionic · Xamarin → Flutter + embedded AI
The only Spanish agency in Google's official Flutter directory. We migrate your existing app without losing functionality, no big-bang, and we use the migration to embed agents, RAG and LLMs where they create real value. Process proven across +100 projects. Result in 3-4 months · Up to 40% lower maintenance cost.
Companies that already trust Dribba
Respuesta directa
Migrar de nativo o React Native a Flutter reduce coste de mantenimiento 30-50% y unifica iOS+Android en un solo codebase. Las migraciones parten de 40.000 € (apps medias) y se sitúan habitualmente en 60-150k €; auditoría técnica inicial 4-8k €. Se hace en paralelo con la app actual en producción para evitar downtime.
+100
Apps in production
40.000 €
From, medium-complexity apps
3-4 meses
Medium app, start to finish
1º
Google Flutter Partner in Spain
Why migrate
What you gain by switching to Flutter.
Each technology has its particularities. Here's what you can expect depending on where you're coming from.
A single codebase
iOS and Android from the same repository. A sprint of changes affects both platforms simultaneously. The team shrinks and speed increases.
40%
Faster development
Hot reload in seconds, no recompilation. Iteration cycles are 40% faster compared to separate native development.
30.000+
Mature ecosystem
Over 30,000 packages on pub.dev. Google and the community maintain plugins for almost any integration: BLE, NFC, maps, payments, camera.
True native performance
Flutter compiles to machine code, no JS bridge, no WebView. The result is indistinguishable from a native app in Swift or Kotlin.
Pixel-perfect UI on any device
Flutter renders with its own graphics engine (Impeller). Animations are smooth at 60/120fps and the design is identical on iOS and Android.
Decisión
¿Cuándo migrar a Flutter?
Migrar cuesta, y mantener la app actual también. Estos son los cuatro escenarios en los que, por nuestra experiencia con +100 apps en producción, una migración a Flutter devuelve la inversión en menos de 12 meses.
Mantenéis dos codebases nativas iOS + Android
Cada feature se construye dos veces. Si el roadmap crece y el equipo no puede escalar al mismo ritmo, Flutter elimina esa duplicación sin renunciar al look nativo.
Umbral → Coste mensual de mantenimiento > 1 FTE dedicado a paridad
React Native os está bloqueando en rendimiento o librerías
El bridge JS ↔ nativo, cambios bruscos en la New Architecture y librerías abandonadas os están forzando patches constantes. Flutter tiene motor propio (Impeller) y ecosistema maduro.
Umbral → Más de 3 bugs de plataforma al trimestre sin solución upstream
Vais a añadir canales: web, desktop, embedded o kiosko
Flutter es hoy cross-platform real (móvil + web + desktop + embedded). Migrar ahora evita construir cada canal desde cero con un stack distinto.
Umbral → Roadmap a 12 meses incluye > 1 canal nuevo
El equipo no puede reemplazar a quien mantiene la app
Si Swift/Kotlin/Xamarin dependen de 1-2 personas y no encontráis relevo senior en el mercado, Flutter reduce el riesgo de bus factor a la mitad: el pool de talento Dart es mayor y más joven.
Umbral → Riesgo de bus factor en un ingeniero concreto
Coste y plazos
Cuánto cuesta y cuánto tarda.
Rangos honestos derivados de más de 20 migraciones reales. La auditoría técnica inicial (4.000-8.000 €) define el presupuesto exacto antes de firmar nada.
| Complejidad | Señales | Plazo | Inversión |
|---|---|---|---|
| Baja | 5-10 pantallas, pocas integraciones nativas, sin SDKs propietarios | 3-4 meses | 40.000-60.000 € |
| Media | 10-25 pantallas, login federado, pagos, push, analítica, CI/CD | 4-6 meses | 60.000-100.000 € |
| Alta | 25+ pantallas, BLE/NFC, mapas, offline-first, SDKs bancarios/sanitarios | 6-12 meses | 100.000-150.000 € |
Incluye auditoría, arquitectura, implementación, QA, release paralelo y transferencia de conocimiento al equipo interno. No incluye licencias de terceros ni servicios cloud.
Starting point
We migrate from any stack.
Each technology has its particularities. Here's what you can expect depending on where you're coming from.
React Native
“The JS bridge limits performance. Outdated libraries. Upgrading RN every version is a nightmare.”
- JS business logic partially reusable
- Navigation and UI components are rewritten
- Native plugins require Flutter equivalent
- Functional tests migrate with adaptation
Swift / Kotlin nativo
“Two repositories, two teams, twice the bugs. Every feature developed twice, never exactly the same.”
- More effort, more gain, a single team
- Native business logic is ported to Dart
- UI is rebuilt, pixel-perfect guaranteed
- 50% team size reduction
Ionic / Capacitor
“WebView performance that hurts the experience. Animations that don't hit 60fps. Web that doesn't feel native.”
- Web components don't migrate (rewritten in Flutter)
- Porting JS business logic to Dart is straightforward
- Performance gain very visible for users
- Lower technical complexity to get started
Xamarin / .NET MAUI
“Xamarin is end-of-life. MAUI has maturity limitations. Microsoft's mobile ecosystem is shrinking.”
- C# → Dart: small adaptation curve for the team
- Business logic ports with few changes
- Xamarin/MAUI UI rewritten in Flutter widgets
- Access to pub.dev ecosystem with +30k packages
Process
No big-bang, no surprises.
01
Code and architecture audit
We analyse the current code: technical debt, critical dependencies, existing tests, backend APIs and coupling to the native platform. We deliver a risk report and a migration plan.
1-2 weeks
02
Flutter architecture definition
We design the Flutter project architecture: folder structure, state management (Riverpod/BLoC), navigation, dependency injection and team conventions.
1 week
03
Incremental module-by-module migration
We migrate module by module, prioritising by impact and risk. Each sprint delivers verified functionality. No big-bang, there's always a working version.
Per sprint
04
QA and regression
Manual testing on real devices (iOS and Android), automated integration tests and performance validation with Dart DevTools. No silent regressions.
Continuous
05
Release and handover
Publication on the App Store and Google Play, architecture documentation, training sessions for the client's team and post-launch support.
1 week
What they ask before signing
The six sentences that come up in the audit.
And what we answer. Four come from whoever owns the tech, two from whoever owns the business.
“If we stop to rewrite, the business stops with us.”
It doesn't stop: the migration runs in parallel and the current app stays in production. Your team can keep fixing bugs in it while the new one advances. No big bang.
“We're going to lose functionality along the way.”
We migrate module by module and every sprint ships functionality verified on real devices, iOS and Android. There's always a working version; whatever isn't migrated stays where it was.
“What about the backend? We can't touch it right now.”
It isn't touched. That's the advantage: Flutter consumes the same REST, GraphQL or WebSocket APIs you already have. This is a client migration, not a platform one.
“My team doesn't know Dart.”
Not needed to start: we do the migration. And we recommend your team joins from day one, because the handover includes architecture documentation and training sessions.
“We lose every test we had.”
Business-logic tests get ported if they're separate from the UI. UI tests get rewritten, and the dossier records what was ported and what wasn't.
“I can't justify the spend if the app already works.”
If it works well, your team is senior in Swift or Kotlin and there's no cost or new-platform pressure, migrating may be the wrong call, and we'll say so in the audit. The argument is the cost of maintaining two codebases, not novelty.
What you keep
The dossier, not just the repository.
A migration that only ships code leaves the “why” in the head of whoever did it. This is the folder that sits next to the project.
It exists so your team can carry on without us: the architecture explained, the decisions justified and the training done.
01-auditoria/
auditoria-codigo.mdCTOTechnical debt, critical dependencies, tests worth porting and coupling to the native platform.orden-de-migracion.mdBusinessThe order each module is migrated in, and why: impact first, risk second.riesgos.mdBusinessWhat could break the deadline, like an SDK with no equivalent or a native integration, and what we do if it happens.
02-arquitectura/
arquitectura-flutter.mdCTOFolder structure, state management, navigation and dependency injection: decided and written down.apis-por-pantalla.mdCTOWhich API each screen consumes. Backend APIs don't change, and here they are on paper.
03-calidad/
tests-portados.mdCTOWhat gets ported from the current test suite and what gets rewritten, with the reason for each.rendimiento.mdCTOMeasured with Dart DevTools before and after, screen by screen. No blind regressions.
04-traspaso/
release-y-tiendas.mdCTOSigning, publishing and what each store looks at. So you can ship the next release yourselves.formacion.mdBusinessThe architecture explained for someone joining, plus the outline of the training sessions.
When do we NOT recommend migrating?
If your native app works well, the team is senior in Swift or Kotlin, and you're not under pressure to cut costs or expand to new platforms, migration may not be the best investment. Also if the project is nearing end of life or the maintenance budget is very limited. We'll tell you honestly in the initial audit.
Frequently asked questions
Everything you're wondering before deciding.
It depends on the complexity of the original app. An app with 5-10 main screens can be migrated in 3-4 months. Complex apps with deep native platform integrations may require 6-12 months. The initial audit gives us a precise timeline.
Yes, and it's the recommended approach. The migration runs in parallel. The client's team can keep fixing critical bugs in the original app while we build the Flutter version. We coordinate releases to minimise divergence.
Backend APIs don't change, that's the advantage. Flutter consumes the same REST, GraphQL or WebSocket APIs as the original app. Only the presentation layer and UI logic are rewritten.
Not to get started. We handle the full migration. But we recommend the client's team gets involved from the beginning to absorb the knowledge. Dart is very similar to TypeScript and Kotlin, the learning curve is short for experienced developers.
Unit tests for business logic are ported if they are well separated from the UI. UI tests (snapshot, instrumentation) are rewritten in Flutter's testing framework. If coverage is low, we take the opportunity to build it from scratch.
Migrations start at €40,000 for medium-complexity apps. The typical range is €60,000-€150,000. The key factors are the complexity of the original app and the volume of native integrations. The initial technical audit (usually €4,000-€8,000) defines the exact budget.
The technical audit
Three questions. The answers tell us whether migrating is the right call.
The audit is the first step and it ends with a realistic plan, with timelines and budget. If the conclusion is not to migrate, it says that too.
Where are you coming from, and how many screens does the app have today?
That sets the effort range. React Native and Xamarin have nothing in common.
Which native integrations can't be lost?
An SDK with no Flutter equivalent is the one risk that can change the recommendation.
Is there a date on the calendar: a release, a funding round, a new market?
It decides whether the migration runs against a deadline or module by module at the team's pace.
o
More about Flutter at Dribba