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 .
Read moreCan I use Flutter in existing app?
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.
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