As usual run flutter pub get
.
Make sure to run the app in release mode to avoid any performance penalties from debug mode. (Note: release mode is not supported on the iOS simulator, a real device is required.)
To run in release mode with Android Studio connect a device or start an emulator, then Run > Flutter Run 'main.dart' in Release Mode.
Or run flutter run --release
.
To further improve performance, make sure to disconnect dev tools. E.g. stop the app on the device and launch it again.