Scott Forstall combined Steve Jobs's sensibilities and obsessive attention to detail with a deep, working background in software engineering. He championed UI usability and responsiveness, spearheaded accessibility initiatives out of care rather than for PR, and led the OS X, iOS, and Safari teams through arguably their best and most reliable years.

Scott Forstall is why the iPhone was the iPhone. Tony Fadell was almost why the iPhone was an iPod.