In this case I'd say the best reason why iOS because Apple is both a Hardware and Software manufacturer in alone.This one does not sympathize Apple had myself just using multiple versions of the Android comes to realize that it is still in it.
Here's where I think the reason is because Apple iOS is both a manufacturer of Hardware and Software on a single Apple does not favor this, but I did use several versions of Android, it is enough to recognize what it is.
Here I iOS best, because they Apple is both the manufacturer and Hardware Software in one This is not to Apple side. , I myself have used Android for many generations, I can know what it is.