Michael Tchao left Apple 15 years ago and was a key developer on the Newton platform, which Apple chief executive Steve Jobs scrapped on his return to the company.
Tchao has now been hired back from a job at Nike, and will report to Apple's senior vice president of product marketing, Phil Schiller, according to reports in The New York Times.
Tchao has the "scars and the great ideas about tablet computing", according to a former colleague at Apple.
Apple is widely expected to enter the lucrative tablet PC market with a 10in unit this year or early in 2010.
Taiwanese manufacturers are reportedly providing touch screens for Apple, and the possibility of Apple's adopting the Intel Atom processor for a tablet device was discussed at last week's Intel Developer Forum.
Tchao is credited with selling former Apple chief executive John Sculley on Newton, especially the handwriting recognition system which was initially lampooned but later proved to be increasingly effective. If a modern recognition system is included on a tablet it could be a very powerful selling point against rival netbook platforms.
Apple has confirmed Tchao's appointment as vice president of product marketing but has said no more. Tchao spent nearly a decade at Apple in the firm's Personal Interactive Electronics division, and a similar period at Nike designing iPod tie-in products.