I'm reading the App Thinning (iOS, tvOS, watchOS) section of the Apple's App Distribution Guide. It describes App Thinning and its components, but I don't find if the developer needs to do something to take advantage of this feature, or if it is automatically handled...
Thanks in advance
Submit bitcode to the app store and and you are fine. Apple takes care of it from there. This answer has details on how enableing bitcode works.