In his time running Apple, Tim Cook has been more like the "president of a country, not a company," according to Deepwater Asset Management's Gene Munster.

Cook's predecessor, Steve Jobs, is considered one of the great product innovators in modern American history. But the role has been a very different one since Jobs stepped down in 2011, shortly before he died from cancer, and tapped Cook to take over.

With his run as CEO coming to an end on Sept. 1, Cook's legacy will be one of tremendous value creation — Apple's market cap increased from about $350 billion to $4 trillion on his watch — even if the company's products were more evolutionary than revolutionary during his 15-year run.

That Cook, 65, is handing the reins to longtime hardware boss John Ternus is no great surprise. Multiple news outlets profiled Ternus in recent months, with The New York Times running a story in January headlined, "The Man Who Could Be Apple’s Next C.E.O."

Still, the move is taking place "about two years earlier than what I was expecting," Munster, managing partner at Deepwater, told CNBC's "Closing Bell: Overtime" after the news broke Monday.

Munster said Cook has cleverly navigated the Trump administration's tariff policies, which posed a particular threat to Apple because of how much the company counts on China for the manufacturing of its devices.

Far from suffering since Trump's second White House term began in January 2025, Apple's stock is up about 20%, and Cook hasn't been shy at all about cozying up to the president in ways meant to charm the commander in chief.

In August, Cook joined Trump at an event in the Oval Office touting a new $100 billion investment commitment by Apple to American manufacturing, and gifted the president a gold and glass plaque.

"Thank you all, and thank you, President Trump, for putting American innovation and American jobs front and center," Cook said at the event, which brought Apple's total planned spend to $600 billion in the U.S. over the next five years. 

Investors have been handsomely rewarded for sticking with Cook.

Apple's stock is close to 20 times higher than it was when he took over, while the S&P 500 is up about sixfold over that stretch. Most company analysts and industry experts attribute Cook's success to his rigor and financial discipline rather than to product innovation.

"Building on Steve Jobs' visionary product leadership, Tim will likely be remembered for his operational leadership — transforming and scaling Apple globally, deepening its services platform, strengthening its supply chain, and making the company more operationally resilient and shareholder-focused," said Rick Wargo, managing partner at executive search and leadership consulting firm Boyden.

Revenue almost quadrupled under Cook, climbing to more than $400 billion in the latest fiscal year. Cook is best known in Silicon Valley as an operations guru, revamping Apple's supply chain after joining in 1998 as an executive vice president of worldwide sales and operations.

When he arrived, Apple was near bankruptcy. Years later, he'd become one of Jobs' top lieutenants and was elevated to the role of operations chief in 2005, two years before the launch of the iPhone.

Cook has continued to benefit from the popularity of the iPhone, which has maintained its dominance for almost two decades in a growing smartphone market. He's also credited with making some key moves to diversify Apple's business and capitalize on the company's mammoth user base, which now amounts to 2.5 billion active devices across the globe.

In 2014, Cook unveiled the Apple Watch, calling it "the most personal product we've ever made." Then came the AirPods in 2016.

In both cases, Apple was jumping into a very familiar category but was able to charge a premium for a product that was primarily targeted at iPhone users and offered rich enhancements to existing offerings.

Apple's wearables category topped $41 billion in annual revenue in fiscal 2022, accounting for over 10% of total sales that year, and up from $25 billion three years earlier.

But it's been a tough market for maintaining momentum due to a swarm of competition and only incremental new features. The company has also failed to turn its high-priced Vision Pro into a consumer hit, as virtual reality remains a niche market. The base Vision Pro sells for $3,500, while Meta's Quest 3S starts at $350.

Apple's wearables business is now engulfed in a multiyear decline, with revenue falling 4% in fiscal 2025 to $35.7 billion, making up 8.6% of total revenue.

Reports are swirling about what kind of wearable could be next for Apple — weather it's smart glasses, a pendant or something else. In any case, the company is now competing on the device front with legendary designer Jony Ive, who joined OpenAI last year when the ChatGPT maker bought his startup for more than $6 billion.

Ive designed the iPod, iPhone, iPad and MacBook Air. He left Apple in 2019.

Profit-hungry investors are big fans of Cook's push into services, which carry much fatter profit margins than hardware. Long stuck at 38%, Apple's gross margin has been creeping up in recent years, reaching 48% in the latest quarter.

And while the wearables business has been shrinking, the services unit is on a tear. Revenue in fiscal 2025 jumped 14% to $109.2 billion, making up 26% of total sales. Included in the services business are advertising, cloud services, digital content and payments.

Cook has been able to get existing iPhone users to spend more with Apple on subscriptions for Apple TV and AppleCare, as well as by using Apple Pay to buy goods and by purchasing apps.

"Apple's core strength under Cook has been its ability to keep hardware, software, and services tightly integrated into a seamless user experience," said Nitin Seth, CEO of consulting firm Incedo and former operating chief at Flipkart. "That remains one of the company's biggest differentiators."

Cook is known as the mastermind of Apple's supply chain, architecting the company's shift to manufacturing in China roughly 25 years ago and its partnership with Foxconn. Apple's established supply chain is what allowed the company to build products at the scale and price necessary to meet demand, particularly when the iPhone began taking off.

As relations with the U.S. and China soured in recent years, Cook began looking to diversify, and he centered much of that effort on India as well as Vietnam. Apple still is heavily reliant on China, even as it's expanded manufacturing across Asia.

"Substantially all of the Company's hardware products are manufactured by outsourcing partners that are located primarily in China mainland, India, Japan, South Korea, Taiwan and Vietnam,"' Apple notes in the risk factors of its Securities and Exchange Commission filings.

But Cook has found ways to keep Apple flourishing even amid Trump's trade wars.

The U.S. government paused the most draconian Chinese tariffs several times, smartphones got an exemption from tariffs and Cook told investors in mid-2025 that the company was able to rearrange its supply chain to import iPhones to the U.S. from India, where tariffs were lower.

That all ties back to Cook's relationship with the president, which was far from amicable at times during Trump's first term. Cook, along with other top tech execs, attended Trump's inauguration in early 2025, and donated to the inaugural fund. Apple is also one of the corporate donors to Trump's White House ballroom project.

Key to staying in Trump's good graces is Cook's commitment to building in the U.S.

Last month, Apple announced an expansion of its American Manufacturing Program, bringing four new partners — Bosch, Cirrus Logic, TDK and Qnity Electronics — into its domestic supply chain. The companies will manufacture essential materials and components in the U.S. for Apple products sold worldwide, with Apple planning to invest $400 million in the new programs through 2030.

"At Apple, we believe in the power of American innovation and manufacturing, and we're proud to partner with even more companies to produce critical components and cutting-edge materials for our products right here in the U.S.," Cook said in the press release in March.

— CNBC's Jennifer Elias contributed to this report.

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