"cupertino" is the name of a Flutter widget set, not of the native platform controls or L&F. Few Flutter apps are going to use cupertino because the whole goal

"cupertino" is the name of a Flutter widget set, not of the native platform controls or L&F. Few Flutter apps are going to use cupertino because the whole goal of using Flutter is to create cross platform codebases to save development effort. To use an alternative widget set per platform is a huge amount of additional work, and having a cupertino app running on Android is even more of a sore thumb than a material app on iOS.