In a dramatic shake-up at the very top of one of the world's most powerful tech giants, Apple has unveiled a sweeping leadership overhaul that signals the dawn of a new era for the iPhone maker. The Silicon Valley titan confirmed on Monday that its long-serving Chief Executive Officer, Tim Cook, will step aside from his current role and transition into the position of executive chairman - a move that keeps him firmly at the heart of the company's strategic direction while handing over day-to-day control. Stepping into the spotlight is John Ternus, Apple's widely respected hardware chief, who has...