End of an era at Apple: Tim Cook's last day as CEO

JUST IN: Tim Cook steps down as CEO of Apple, ending a 15-year run at the helm of the company.

Tim Cook just worked his last day as CEO of Apple.

Fifteen years at the top, and think about what he inherited. He took over from Steve Jobs in 2011, and half the world said Apple was finished without its founder. Instead, Cook turned it into the most valuable company on earth, built the services machine, put a computer on your wrist, and did it all while being the least dramatic man in tech. He spent his final day at Apple Park, and you can see him here, saying goodbye to the place he ran for a decade and a half.

Jobs built the cathedral. Cook made it print money. Whoever sits in that chair next inherits three trillion dollars of expectations and a fanbase that notices everything.

The hardest act to follow in business just ended its second act. Good luck to whoever opens the third.

This is Sara White, reporting for HIT.