It's been my bread and butter.
Sort of a love/hate relationship, though. Anyone who is a seasoned Apple dev, has been incandescent with rage at Apple, at more than a few points in the relationship.
But the thing I can't forget, is the absolute torrent of derision and abuse from Apple-haters, telling me what a loser I was, for sticking with them.
Funnily enough, I've not felt like hating anyone back. Never worked for me.