Apple mobile hardware boss leaves without explanation

Apple's head of iPhone and iPad hardware left the company last week, with the firm offering no explanation.

Mark Papermaster had joined the company just last year, following a 25 year stint at IBM. Recruiting him to Apple's ranks involved a contract dispute by IBM which delayed his arrival by a year.

Apple has declined to comment on the issue, bar stating that Mac engineering boss Bob Mansfield would assume Papermaster's duties for the time being.

"Mr. Mansfield already manages groups that create many of the key technologies for the iPhone and iPod touch," said Apple spokesman Steve Dowling, "including the A4 chip, Retina display and touch screens."

While any attribution of cause is purely speculative, the departure comes soon after a protracted controversy concerning the iPhone 4's antenna. A design issue saw the phone losing signal for some users if held in a certain way.

Apple's initial response to complaints was curt, but amid mounting profile for the alleged problem, it held a press conference in which it promised free insulating Bumpers to all purchasers of the phone.

However, bloggers have observed that Papermaster had a low profile in the run-up to the iPhone 4's launch. Unnamed sources were also alleged to have claimed that Apple was aware of the antenna bug some two years ago – before Papermaster had joined the company.