Platform embedding

As we’ve seen, rather than being translated into the equivalent OS widgets,
Flutter user interfaces are built, laid out, composited, and painted by Flutter
itself. The mechanism for obtaining the texture and participating in the app
lifecycle of the underlying operating system inevitably varies depending on the
unique concerns of that platform. The engine is platform-agnostic, presenting a
stable ABI (Application Binary
Interface)
that provides a platform embedder with a way to set up and use Flutter.