Apple AAPL-Q on Monday named longtime hardware boss John Ternus as its next CEO, turning to another insider to steer the iPhone maker after Tim Cook as it navigates a world radically altered by artificial intelligence, a technology it has lagged on.

Cook, a supply-chain genius who boosted Apple’s market value by US$3.6-trillion in his 15 years at the helm, will stay on as executive chairman when Ternus takes over on Sept. 1, Apple said in a statement.

Ternus, who joined Apple in 2001, has played a central role in reviving products such as the Mac, which has gained market share against PCs. Though he has kept a low public profile, he has been deeply involved in shaping Apple’s biggest products such as iPads and AirPods.

The transition comes at a crucial time for Apple. After years on top of the most-valuable company scoreboard, Apple has lost its crown to AI chipmaker Nvidia, as investors have fretted over its lack of innovation in the technology that is changing how people work, create and get information.