Android has gone through quite a few changes during its short 6 years of life. The Android that drives most of the world's smartphones of today would be almost unrecognizable to what was launched in late 2008. We've seen massive visual changes, expansion to almost every conceivable form factor, and a completely fleshed-out content ecosystem for multimedia and apps. As the operating system matured, some elements have successfully grown with it, and others have become dead weight.
Jack And Jill Are Google's New Compilers For Android App Developers was written by the awesome team at Android Police.