I haven't run across anything like that in this book, but I do know there's at least two other Jobs bios -- Steve Jobs: The Man Who Thought Different, and Becoming Steve Jobs. I used the "search inside this book" feature on Amazon for those books but didn't see any mention of the Devil. (And I just now searched this book and didn't get a hit.) It wouldn't surprise me that people thought that, though. Jobs had an almost preternatural gift for putting things together in a product that people would want. He could also be a really garbage disagreeable pig person, for real. He screwed his friends out of bonus money and stock options, was an arrogant asshole, and how he didn't manage to alienate every single person he ever met I'll never know.

And yet. It's a fascinating story, and Isaacson tells it very well. :D