One manufacturer vs. multiple, of course the android is going to come out ahead.
I will say that Google has done a better job at innovating the OS then Apple has. It seems through the years Apple has been reactive to the market and not proactive. Notification center, multitasking, lock screen notifications, etc.
Android is only now getting lock screen notifications natively in Android L.
And I'd argue all those things mentioned are done better in iOS anyhow. I'm not sure how "reactive" they've been given we have no idea what has been in the pipeline or for how long. It just seems to me Apple prefers to let a feature mature before releasing it, with the obvious exception being Maps as customer input was absolutely essential in building a great maps product.
Android has been slow to adopt certain things in its own right. Just last year Google Now gained the ability to create reminders and tasks. Just last year they added Play Games. And Android L will bring a slew of features I'm excited about being an iOS-fan.
All-in-all, both OSes have been quick on some things and slow on others. Android has the marketshare advantage because its on a much larger variety of devices available to a larger number of people at a vast number of price points.
As far as market leadership goes? Apple is still very much out front with Android. The iPhone isn't going away anytime soon - in fact, I think this fall/winter for Apple will be the biggest quarter anyone's ever seen. They don't usually miss on their estimates of sales and rumor has it they are readying nearly 100 million iPhones for the rest of this year. If they sold that many iPhones, it would be unreal and would put a relatively sizable dent in marketshare numbers - especially given the relatively small number of options available for those who buy iOS.