There is evidence that Steve Jobs thought up the iPad as early as the early 1980s. Recently, I started reading one of the definitive books on Apple and Steve Jobs in the early days of Apple. It is written by Michael Moritz, who was a journalist and then went on to become one of the most successful venture capitalist in the United States (At Sequoia Capital). The book, Return to the Little Kingdom, was originally released in 1984 as “The Little Kingdom: The Private Story of Apple Computer.” In the above link is the revised version of that book released in 2009.
Here is an interesting fact from Moritz’ book. It seems even then when Apple’s main new computer was the Lisa, Steve was dreaming of something that would eventually become the iPad. Here is a passage from Moritz’ book when Steve Jobs was speaking to a group of students at Stanford:
He told the students about the company’s Lisa computer, disclosed his dream of putting a computer in a book, and promised, “We won’t’ put garbage in a book because our competitors will do that.”
(page 1445 of 1762 in iPhone edition of iBook of Return to Little Kingdom by Michael Moritz)
It sounds to me like Steve Jobs was envisioning the iPad. “Putting a computer in a book,” sounds like the concept of the iPad. The iPad weighs and feels like a book. It is very possible that the iPad we have today is something Steve Jobs was shooting for in the early 1980s.