Tim Cook took on the daunting task of succeeding Steve Jobs as Apple CEO — and led the tech giant to even greater heights. Vanishingly few people would have dared follow Jobs , Apple's iconic cofounder who reshaped how the world works with revolutionary devices such as the iPod and iPhone. Yet Cook pulled off what few thought possible: taking Apple to the next level . During his nearly 15 years in charge, Apple has roughly quadrupled its annual net sales and net income to over $400 billion and $