(VIDEO) John Ternus Officially Becomes Apple CEO Today as Tim Cook Steps Aside After 15 Years at the Helm

CUPERTINO, Calif. — John Ternus formally became Apple's chief executive officer Tuesday, taking over from Tim Cook in the company's most significant leadership transition in more than a decade as Apple heads into a pivotal product launch and an intensifying race in artificial intelligence.

Cook's final day as CEO was Monday, closing out a tenure that began in August 2011 when he succeeded Apple co-founder Steve Jobs. Cook posted a farewell message to the Apple community on X, writing, "Sending lots of love to the Apple community on my last day as CEO. My title changes tomorrow, but the love I have for the Apple community never will." As of Tuesday, Cook transitions into the role of executive chairman of Apple's board of directors, a position in which he is expected to continue assisting the company with certain responsibilities, including engagement with policymakers around the world.

Apple first announced the transition plan in April, saying the change had been approved unanimously by the company's board of directors following what Apple described as a thoughtful, long-term succession planning process. In the company's original announcement, Cook reflected on his time leading Apple. "It has been the greatest privilege of my life to be the CEO of Apple and to have been trusted to lead such an extraordinary company," Cook said at the time. "I love Apple with all of my being, and I am so grateful to have had the opportunity to work with a team of such ingenious, innovative, creative, and deeply caring people."

Board chairman Arthur Levinson praised Cook's tenure in the same announcement, crediting him with transforming Apple into what Levinson called the world's best company. "Tim's unprecedented and outstanding leadership has transformed Apple into the world's best company. He's introduced groundbreaking products and services time and again, and his integrity and values are infused into everything Apple does," Levinson said. "On behalf of the entire board of directors, we are incredibly grateful for his countless contributions to Apple and the world, and we are thrilled he will now be executive chairman."

Ternus, 51, joined Apple in 2001 and has spent nearly a quarter-century at the company, most recently serving as senior vice president of hardware engineering since 2021. He also joins Apple's board of directors effective Tuesday. According to Apple's own regulatory disclosures, the board believes Ternus's deep technical background and product focus make him well-suited to lead the company through its next chapter. Levinson said the board views Ternus as the right leader to build on Cook's foundation. "We believe John is the best possible leader to succeed Tim and as he transitions to CEO we know his love of Apple, his leadership, deep technical knowledge, and relentless focus on creating great products will help," Levinson said in April's announcement.

Ternus's path to Apple's top job traces back to the University of Pennsylvania, where he earned a bachelor's degree in mechanical engineering in 1997 while also competing as a swimmer. At 51, he becomes CEO at roughly the same age Cook was when he took over from Jobs in 2011, a similarity that industry observers, including reporting from Fortune, have suggested may have factored into the board's preference for a leader capable of providing long-term stability at the helm.

Ternus's rise within Apple has followed a gradual, closely watched trajectory in recent years. Bloomberg's Mark Gurman reported as early as 2021 that Ternus was viewed as a likely eventual successor to Cook, and subsequent reporting throughout 2025 and early 2026 described Apple's public relations efforts increasingly placing Ternus in more prominent, public-facing roles, including product launch events and store visits. Late last year, oversight of Apple's design teams was also transferred to Ternus, a responsibility historically held by only a small handful of top Apple executives, including Cook himself from 2015 to 2017, longtime design chief Jony Ive until 2019, and former Chief Operating Officer Jeff Williams from 2019 until his departure from the company in 2025.

Cook's 15-year tenure as CEO encompassed a substantial expansion of Apple's product and services portfolio, including the introduction of the Apple Watch, AirPods, Apple Pay and Apple Vision Pro, along with the Mac's multiyear transition away from Intel processors to Apple's own custom silicon. Cook also steered Apple deeper into recurring subscription revenue, overseeing dramatic growth in the App Store alongside the launches of Apple Music, Apple TV and expanded Apple Maps functionality. Under his leadership, Apple's market capitalization grew from roughly 350 billion dollars to more than 4 trillion dollars.

Ternus takes over at a consequential moment for Apple. His first major public moment as CEO is expected to come just over a week from now, at Apple's Sept. 9 "Surprise and Shine" event in Cupertino, where the company is widely expected to unveil the iPhone 18 Pro, iPhone 18 Pro Max and its first foldable iPhone. Analysts covering the transition, including those cited by financial research firm TradingKey, have said Ternus's central challenge will be translating Apple's hardware strengths into a meaningful competitive position as the broader technology industry increasingly competes on artificial intelligence capabilities, an area where some analysts have said Apple has appeared to lag behind rivals in recent product cycles.