The AndroidManifext.xml has this code:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.skeleton">
<application
android:label="skeleton"
android:name="${applicationName}"
android:icon="@mipmap/ic_launcher">
On what real value the applicationName is interpolated?
This value is set by the Flutter Gradle plugin.
It can have 2 value :
If you have multidex enabled and your app has a minSdk less than 20, this value will be io.flutter.app.FlutterMultiDexApplication.
Else, it will be android.app.Application.
You can override this value by setting the base-application-name property (in the gradle.properties of your android folder for example).
Source : https://github.com/flutter/flutter/blob/master/packages/flutter_tools/gradle/flutter.gradle#L261
Remember that you can always inspect the resulting APK (in build/app/outputs/flutter-apk) to see what value is in the final Manifest. Or you can just read the merged manifest in build/app/intermediates/merged_manifests/debug/AndroidManifest.xml.
These are defined in your build.gradle file.
Read more about it here
Edit: i missed it was about flutter. This is what the flutter documentation has to say:
Defaults to the value of Title.title, if a Title widget can be found. Otherwise, defaults to Platform.resolvedExecutable.