Has this always been the case?
Lorenzo Sciandra

A Flutter project has always had iOS and Android folders to create IPA/APK files for the respective platforms. The platform-specific behaviour is also implemented in these folders and called through platform-channels. I personally am writing a tutorial for those but in the mean time, I recommend https://flutter.io/platform-channels/ for implementing them. Be sure to reach out if you run through any problems while doing it.