During development, you’ve been building, debugging, and testing
with debug builds. When you’re ready to ship your app to users
on the App Store or TestFlight, you need to prepare a release build.
At this point, you might consider obfuscating your Dart code
to make it more difficult to reverse engineer. Obfuscating
your code involves adding a couple flags to your build command.

In Xcode, configure the app version and build:

Open Runner.xcworkspace in your app’s macos folder. To do this from
the command line, run the following command from the base directory of your
application project.
    
open macos/Runner.xcworkspace

Select Runner in the Xcode project navigator, then select the
Runner target in the settings view sidebar.

In the Identity section, update the Version to the user-facing
version number you wish to publish.