I'd be happy to allow Android users to call a 3rd party app a "feature of the operating system" like the author did, as long as he's will to include iOS 3rd party apps as features of iOS. We might as well compare oranges to oranges.
He doesn't actually call the 3rd party apps features of the OS. He states the features that are available to both OSes and notes those that are via 3rd party apps. Some prefer everything to be built into the OS while others prefer an OS that simply allows others to create/enhance the functionality. There are pros and cons to both approaches.
