updated 12:36 am EDT, Thu April 10, 2014
Multiple sources confirm retirement was announced internally weeks ago
Earlier reports that senior iOS engineer and leader of Apple's Human Interface Group Greg Christie was leaving the company over tension with software and hardware design chief Sir Jonathan Ive appear to have been half-correct. Multiple sources have come forward to note that Christie is retiring, but had announced the move weeks ago internally.
Apple took the unusual step of providing statements to various news outlets that "Greg has been planning to retire later this year after nearly 20 years at Apple. He has made vital contributions to Apple products across the board, and built a world-class Human Interface team which has worked closely with Jony for many years." Christie came to Apple in 1996 along with the return of Steve Jobs as CEO of the company.
Christie will be staying on with Apple for an unspecified time longer (some report until the end of the year), and just testified on behalf of the company during its second patent trial against Samsung. None of the confirmations rule out the possibility that Christie and Ive have had a falling out, but TechCrunch reported that Christie's retirement was announced to engineers and executives early so that the company could effect a smooth transition as the Human Interface group begins reporting to Ive rather than Craig Federighi as it does now.
Pundit John Gruber of Daring Fireball has said that his sources acknowledge that Christie and Ive have disagreed on various issues, but that this has nothing to do with the retirement. Christie, as one of the team that created the initial OS X-based "iPhone OS" (now known as iOS) came to Apple along with Jobs when he returned to the company in the late 90s. He was also part of the team that created the iOS 7 update, and was in charge of briefing developers on the change at last year's Worldwide Developer's Conference.
"The basic gist I've heard is that Christie is a guy who's been in a high-pressure, high-profile job for 18 years, most of it reporting to Steve Jobs," Gruber wrote. "He's made a lot of money and is ready to enjoy it." While it is possible that the various sources are simply bolstering the company PR line, it can be said that Christie's decision not to leave immediately does suggest that the early reports may have been exaggerated.