John Ternus took over as Apple's chief executive on Tuesday, ending Tim Cook's 15-year run at the top of the world's most valuable technology company.
Cook, 65, moves to the newly created role of executive chairman, where he is expected to focus on relationships with governments and policymakers around the world.
Arthur Levinson, who has chaired Apple's board for the past 15 years, becomes lead independent director, while Ternus joins the board itself.
In a letter to Apple staff marking his last day as chief executive, Cook wrote: "This place is proof that culture triumphs over everything."
A hardware chief inherits an AI problem
Ternus, 51, joined Apple in 2001 and has spent more than two decades climbing its engineering ranks, becoming senior vice president of Hardware Engineering in 2013 and joining the executive team in 2021.
He takes charge of a company that has struggled to keep pace with rivals such as OpenAI on generative AI, after promised upgrades to Siri and other AI features slipped repeatedly under Cook.
Apple shares have still risen by around 17% so far in 2026, helped by strong iPhone sales and market share gains over Android rivals hit harder by supply problems.
The company's market value climbed to $4.6 trillion during Cook's tenure, driven largely by the enduring popularity of the iPhone.
Supply squeeze adds pressure
Ternus also inherits a worsening global shortage of memory chips, caused by data centres buying up RAM and storage to power the AI boom.
Apple raised prices on MacBooks and iPads in June because of the shortage, and analysts expect similar increases for iPhones early in Ternus's tenure.
Some industry watchers believe Apple's expected foldable phone, dubbed the "Ultra" by some reports, could cost as much as $2,500 when it launches.
Leadership reshuffle beyond the top job
The transition has coincided with wider changes among Apple's senior ranks.
The role of senior vice president of government affairs has been left vacant, and Phil Schiller is stepping back from day-to-day responsibility for the App Store and Apple's product events, according to Bloomberg.
Schiller, who has been at Apple since 1987, will remain with the company but in a reduced capacity.
First test comes in days
Ternus faces his first major public test on September 9, when Apple holds its autumn hardware event and is expected to unveil new iPhones alongside the foldable device.
The succession itself was announced in April, when Apple's board said the transition would be handled in a "thoughtful" and gradual way over the following months.
Analysts including Gene Munster of Deepwater Asset Management have suggested Ternus's engineering background and his years spent recruiting Apple's technical talent could prove valuable as the company tries to define what comes after the smartphone.
Cook is expected to keep helping the company manage its relationship with the Trump administration even after handing over day-to-day control, given the ties he built during years of trade and tariff disputes affecting Apple's Asian supply chain.
