Android

Open AndroidManifest.xml (위치: android/app/src/main)

<application
    android:label="App Name" ...> // Your app name here

iOS

Open info.plist (위치: ios/Runner)

<key>CFBundleName</key>
<string>App Name</string> // Your app name here

clean project

flutter clean

or

VSCode인경우 Ctrl(cmd)+Shift+P -> Clean Project