Tim Cook will step down as Apple CEO and be replaced by hardware chief John Ternus

Cook joined Apple in 1998 and became CEO in 2011, succeeding Steve Jobs. He led the tech giant to a $4 trillion market cap

picture alliance / Getty Images

Apple $AAPL said Monday that Tim Cook will step down as CEO on Sept. 1, ending 15 years leading the tech giant that saw him succeed the visionary Apple co-founder Steve Jobs and grow the company to a $4 trillion market cap. John Ternus, Apple's senior vice president of hardware engineering, will become chief executive, and Cook will become executive chairman, Apple said.

Apple's board of directors approved the transition unanimously after what the company called a long-term succession planning process. The handoff will be gradual, with Ternus working alongside Cook before formally assuming the top........

© Quartz