I’ve contacted the developer. In F-Droid full network access is listed as a permission but the Play Store version does not use the permission. (I downloaded from F-Droid and it does not have the permission that F-Droid says it has.) I almost uninstalled it because I saw no need for it to have internet. Glad I discovered that it does not ask for internet.
Dev emailed me this:
" The internet permission is something that Flutter uses for debugging. It appears whoever uploaded the app put the debug build and not a release build. Regardless you should still be safe as the app doesn’t talk to the internet at all when functioning. If you would like to install a release apk that doesn’t have the internet permission declared you can download it using the link below.
He was quick to respond!
F-Droid shouldn’t (under any circumstances) build debug versions of apps. @uniqx you looked at the flutter stuff before, any idea?
The INTERNET permission is explicitly declared in the manifest: https://github.com/SamarthDesai01/RepeatMe/blob/v1.2.4/android/app/src/main/AndroidManifest.xml. That’s why it ended up in the app built by F-Droid.
The Flutter doc says that
flutter build apk builds a release APK by default, so unless the app forces some setting, we are building the release version.