How to Migrate/Convert Existing Android/iOS Apps into Flutter

A quick guide on migrating Android/iOS apps to Flutter

Image by: Milan On: Self create

When Flutter started stirring up cross-platform mobile app development, it caught quite the attention of developers and entrepreneurs. After all, Google’s brainchild Flutter is a remarkable software development kit, enabling the creation of beautiful and high-performing cross-platform apps. Apps built with Flutter not only render a pleasing user experience but also look and feel nearly like native apps.

Not to mention, Flutter lets you build Web, desktop, and mobile apps for as many as six operating systems from a single codebase. We can count the reasons to choose this cross-platform framework and kit all day long. But rewriting an entire application in Flutter all at once does not seem practical.

That is where Flutter’s amazing functionality of integrating it into existing native apps comes in handy. If you want to leverage Flutter’s cross-platform specialties, you can add it to your existing app piecemeal as a library or module. Then, you can also import that module into your existing Android or iOS app to render a part of the app’s UI in Flutter.

Just like that, in a few steps, you can bring the expressiveness and productivity of Flutter into your own app. Now, let us know a little more about adding Flutter to existing Android and iOS apps.

Add Flutter to an existing Android app:

Step 1- Open the existing project

Step 2- New Flutter module wizard

Step 3- Use Flutter Android APIs

Step 4- Build & run

Step 5- Attach & hot reload.

Things that Flutter allows us to do when integrated into Android apps.

• You can add a Flutter SDK hook to your Gradle script to auto-build and import the Flutter module.
• If you want to integrate the Flutter module into your own build system, build your Flutter module into a generic Android Archive (AAR) that also better Jetifier interoperability with AndroidX.
• Use FlutterEngine API for starting and continuing your Flutter environment independently.
• Module import/creation wizard allows you to co-edit Android and Flutter projects in Android Studio.
• It supports apps built with Java and Kotlin both.
• Flutter plugins can be integrated into the preexisting platform and used for Flutter modules to interact with the platform.
• Using the flutter attach function from an IDE or the command line, you can connect to an app that contains Flutter and debug it or reload it using stateful hot reload.

Add Flutter to an existing iOS app:

Step 1- Open existing project

Step 2- Create Flutter Module

Step 3- CocoaPods Install

Step 4- Use Flutter iOS APIs

Step 5- Build & run

Step 6- Attach & hot reload.

Things that Flutter allows us to do when integrated into iOS apps.

• Add a Flutter SDK hook to your CocoaPods and Xcode build phase to auto-build and import the Flutter module.
• It allows you to create a Flutter module into a generic iOS Framework so that you can integrate the module into your own build system.
• FlutterEngine API for starting and persisting your Flutter environment independently of attaching a FlutterViewController.
• It also supports both types of iOS apps Objective-C and Swift.
• Let Flutter modules use Flutter plugins to interact with the platform.
• Using the flutter attach function from an IDE or the command line, you can connect to an app that contains Flutter and debug it or reload it using stateful hot reload.

If you are confused as to when you should opt for this transformation, here are some cases;

1. When you have an already existing application in either Android or iOS and it is due for an update.
2. Your existing application is facing technical issues, and you anyhow have to work on releasing an update.
3. When you wish to go with the trend and wish to release a fully-functional application.

However, it is worth it to migrate to Flutter to deliver an exceptional user interface and experience design. But you have to be careful in many areas. Therefore, it is recommended to hire Flutter developers with hands-on experience in migrating native apps to Flutter.

Let me know if you are looking forward to upgrading your app with Flutter. It would be our pleasure to help you!

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