PART 2 - FOUR HIDDEN CHIMNEYS CHAPTER 8: THE SHIELD OF SCREWTAPE Everything Is a Computer

"Tony Fadell’s early iPhone path built outward from the iPod, while Scott Forstall pursued the riskier route of shrinking Mac OS X onto a phone."

Vogelstein's account describes Fadell's team working from an iPod-derived P1 system while Forstall's team independently tried to make OS X run on the phone.

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