Add-to-app For those situations, Flutter can be integrated into your existing application piecemeal, as a library or module . That module can then be imported into your Android or iOS (currently supported platforms) app to render a part of your app’s UI in Flutter.
Read moreHow can I change my Android to iOS on Flutter?
Use flutter build apk –release for building an Android app. For iOS, use flutter build ios –release and then go to XCode and Archive the app .
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