Android-to-Flutter App Migration
Bring your existing Android app to Flutter with a migration plan built around your features, backend, and users. I’m Rahim Ullah. I help businesses move from Java or Kotlin applications toward a shared Android and iOS codebase, with clear scope, testing, and handover.
Based in Islamabad, Pakistan · Working with clients worldwide.
Technologies
- Flutter
- Dart
- Java
- Kotlin
Target platforms
- Android
- iOS
When migration makes sense
Your Android product needs iOS support
Bring an established product to another platform while planning for the differences in permissions, integrations, and release requirements.
Separate mobile codebases are difficult to maintain
Consider a shared Flutter implementation when coordinating features and fixes across separate apps has become difficult.
The mobile interface needs a refresh
Review navigation and screen behavior alongside the migration. Keep familiar flows or agree on a redesign as a separate part of the scope.
Your existing backend should keep supporting the app
Build a new mobile client around established services where their APIs and authentication meet the new requirements.
Migration is not automatically the right choice. Deep platform-specific functionality, a stable Android-only product, or a limited budget may favor improving the native app. I review those constraints before recommending a rebuild.
What the migration includes
I define the work around your existing product and target platforms. The agreed scope identifies required features, integrations, exclusions, and acceptance criteria; not every integration belongs in every quote.
Application and source review
Review the current code, dependencies, backend, and release setup to identify reusable services and migration risks.
Screen and feature inventory
Document screens, workflows, edge cases, and the behavior that needs to carry forward.
Flutter interface and architecture
Implement agreed screens, navigation, state management, and application structure in Flutter and Dart.
Existing API and backend integration
Connect the Flutter app to approved services and identify any missing or incompatible endpoints.
Scoped application integrations
Rework agreed authentication, notifications, media, and device features, accounting for Android and iOS differences.
Testing and release preparation
Test agreed workflows on target platforms and prepare the build and submission tasks included in the scope.
Source code and technical handover
Provide the Flutter project, agreed setup documentation, and a record of known limitations.
Optional work, agreed separately
A redesign, new features, backend changes, and infrastructure migration are not automatic parts of a mobile migration. I assess and estimate these separately before including them.
What happens to your backend and user data?
Laravel, Node.js, Firebase, Supabase, and other existing backends may remain in place if their interfaces meet the new app’s requirements. Rebuilding the mobile interface does not inherently require replacing the server database.
- Accounts and application data
- I review existing accounts, authentication behavior, local device data, uploads, and API compatibility individually. Server data and data stored only on a device need different migration plans.
- Changes to stored data
- Any planned data changes need an appropriate backup, validation, and recovery plan. Preservation is a requirement to assess and test, not an automatic guarantee.
- Platform behavior and access
- Push notifications, deep links, signing, permissions, and platform-specific features need explicit checks. Existing Android configuration does not automatically cover iOS.
Java or Kotlin to Flutter migration is engineering work, not a one-click source-code conversion. I plan how to rebuild the required behavior; I do not promise zero downtime or zero data loss.
A real migration: Tikdating
- Original application
- I built the original Android app in Java and XML, with profiles, short videos, matching, and conversations.
- New requirement
- The client later requested iOS support for the existing product.
- My contribution
- I migrated the mobile application to Flutter, integrating with the existing Laravel backend and administration system and Firebase integrations.
- Resulting implementation
- Flutter is now the mobile implementation for Android and iOS. The case study explains the original Android work and the later migration.
A migration process with review checkpoints
This is my proposed workflow. I adapt the checkpoints and deliverables to the application after the initial review.
- 01
Review the existing application
Understand source code, features, integrations, backend behavior, and target platforms.
- 02
Agree on scope and acceptance criteria
Separate required feature parity from redesign and new functionality. Define how completed work will be reviewed.
- 03
Plan architecture and integrations
Identify reusable services, platform-specific work, and any backend changes that need separate agreement.
- 04
Implement and review in stages
Build the Flutter application in agreed stages, sharing review builds and collecting feedback at checkpoints.
- 05
Test critical workflows
Check authentication, content, applicable purchases, notifications, permissions, and Android and iOS behavior.
- 06
Prepare release and handover
Provide agreed builds, source code, setup documentation, and release assistance. Store approval remains the platform’s decision.
What you receive
Deliverables are agreed before implementation and depend on the selected platforms and scope.
- Flutter source code.
- Agreed Android and iOS build outputs.
- An implemented feature checklist.
- Integration and setup documentation.
- Testing findings and known limitations.
- Technical handover and agreed release assistance.
A project estimate based on your app
I review the application before proposing cost and timing. The main factors are:
- Screen and workflow complexity.
- Source-code quality and access.
- Backend and API readiness.
- Native SDKs and device features.
- Payments, media, offline behavior, and local data.
- Redesign or new functionality.
- Target platforms and release requirements.
Starting a new application instead? Explore my Flutter app development service for broader development work.
Frequently asked questions
Can you migrate an existing Java or Kotlin Android app to Flutter?
Yes, after reviewing its source and requirements. I rebuild the agreed behavior in Flutter rather than automatically translating the code. Tikdating is an example of my Java-to-Flutter migration work.
Can I keep my current backend and admin panel?
Often, if the APIs and authentication support the new app. I check compatibility first and identify any required server changes separately.
What happens to existing users and their data?
That depends on where data lives and how accounts work. I assess server records, sign-in behavior, and local storage, then agree on any migration, backup, validation, and recovery work.
Can the Flutter application support Android and iOS?
Yes. A shared codebase can target both, but each platform still needs configuration, integration checks, and testing. iOS support does not itself mean an App Store release.
Does migration include a redesign?
Only if agreed. The starting scope can preserve existing screens and workflows; a visual redesign or changed user experience is assessed separately.
What happens to payments, subscriptions, and native integrations?
I assess each integration separately. iOS billing, purchase restoration, native SDKs, and device features do not automatically carry over from Android and may need different implementation and testing.
How long does migration take, and what determines the cost?
I estimate after reviewing the app. Workflow complexity, code quality, API readiness, platform integrations, and any redesign affect both effort and timing.
What do you need to review before providing an estimate?
Share an app link or screenshots, desired platforms, key features, and known technologies. I can then discuss private access to source code and API documentation if needed.
Will I receive the source code and handover documentation?
Yes. The agreed handover includes the Flutter source code and setup and integration documentation. Build outputs and release assistance follow the project scope.
Planning to Bring Your Android App to Flutter?
Send a short overview through my existing contact page. Include:
- An app-store link or screenshots.
- The current technology stack, if known.
- Your desired platforms.
- The main features and integrations.
- Whether you need feature parity, a redesign, or new features.
I can discuss source access privately after the initial conversation. Do not send passwords, API keys, or other credentials through the public contact form.