Change default apps, completely customize the user interface / launcher / notification shade (quick settings) / icons / everything, split screen multitasking, notably better notifications.
But if that isn't important (and it's not important for most people), then there isn't much difference between the two. They both are very polished OSes.
He was saying Android performs better in some cases despite the CPUs typically being slower. While the things you listed are of course things Apple doesn't do none of them are really related to tasks and such. I am specifically asking what kind of tasks do people actually do on their Android phone that one can't do on an iPhone.
I suppose split screen multitasking might count but I don't really consider that a task