4. Bob Mansfield's Retirement
Like Scott Forstall's sudden departure, the retirement of Bob Mansfield was one of Apple's biggest executive shake-ups this year.
Mansfield, Apple's senior vice president of hardware engineering and one of the driving forces behind the Mac, iPhone and iPad product lines, was said in June to be transitioning to retirement. He had been with Apple since 1999 and served as the chief Mac engineer since 2005.
Mansfield also had a heavy hand in Apple's mobile products, spearheading both iPhone and iPad engineering. His responsibilities were handed over to Dan Riccio, vice president of iPad hardware engineering, during the several months he transitioned to retirement.