Ten years ago, when we launched the first Android phone—the T-Mobile G1—it was with a simple but bold idea: to build a mobile platform that’s free and open to everyone. To what quantitative fraction is Android still free and open (as in speech), and how much of it has been moved into closed-source containers?
Almost all of it is closed. Since the G1, the following parts are just some of the many that were removed from the open project and replaced with proprietary ones: Launcher, Dialer (the actual phone app), Contacts, Calendar, Email, on-device Search (last open in 2.3.7), and many more. Everything that the user touches or sees is closed source.
With Android P they are doing the same to Java apps that make use of reflection to access non-public APIs or work around bugs due to lack of updates.