Currently, there are three main folders in the Flutter project; android, lib, and ios. The ‘lib’ is important because it takes care of Dart files.
While the Android and iOS folders help in building apps on those respective platforms with the Dart files running on them. Furthermore, they help in adding permissions and platform-specific functionality in the projects.
When running a Flutter project, it builds depending on which emulator or device it is running on, doing a Gradle or XCode build using the folders inside it. As a result, the folders are entire apps that set the stage for the Flutter code to run.
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