After nearly 15 years at the helm of Apple, Tim Cook will step down as CEO of the company on September 1, 2026, and John Ternus, the long‑time head of hardware engineering, will replace him.
Cook will continue to serve as executive chairman of Apple's board.
But perhaps the best way to measure Cook's performance is to look at Apple's stock chart during his tenure; a chart that shows one of the most striking growth periods of a major technology company.
Apple stock rose 2,272 percent
When Tim Cook became Apple's CEO in August 2011 as Steve Jobs's successor, the company's share price was about $13.35; but Apple shares closed at $316.61 on the last trading day before the leadership change.
Thus, Apple's stock value increased by about 2,272 percent during Cook's tenure; a gain that far outpaced the major U.S. stock market indexes over the same period.
Apple's market value also rose from about $347 billion in 2011 to about $4.7 trillion. One estimate suggests that Apple's market value increased on average by roughly $32 million every hour during Cook's tenure.
These figures have made Cook's era one of the most successful managerial periods in the history of the tech industry; especially given that he took over a company many expected would face serious problems after its legendary founder.
Cook did not just make Apple bigger; he changed its business model
Despite the remarkable growth of the iPhone and other products, Cook's most important legacy cannot be reduced solely to hardware sales.
At the start of Cook's tenure, Apple was still a company whose large portion of revenue depended on the cycle of launching new products. The iPhone, iPad and Mac were the main products and the company's financial success was largely tied to the sales of these devices.
Cook gradually changed that model and made services and recurring revenues one of the main pillars of Apple's business.
App Store, iCloud, Apple Music, Apple TV, Apple Pay and Apple News+ are now part of an ecosystem that users pay to use continuously.
In its most recent financial report, Apple said it has more than 1.5 billion paid subscriptions across its platforms. Services revenue in the last fiscal quarter reached $30.7 billion, up 12 percent from the prior year.
Apple at the end of Cook's era is no longer the same company as in 2011
During Cook's leadership, Apple expanded beyond services into new areas such as smartwatches, wireless headphones and mixed‑reality products.
The Apple Watch and AirPods became important products in Apple's ecosystem and allowed the company to reduce its dependence on the iPhone to some extent.
At the same time, Apple developed its manufacturing network and supply chain on a global scale; an area that is one of the main strengths of Cook's management. His expertise prior to becoming CEO was mainly in operations and supply chain, and that background proved useful in running the company.
However, Cook's era was not without its challenges.
The next big challenge: artificial intelligence
John Ternus becomes Apple's CEO at a time when the tech industry has entered a new phase: the era of generative AI and intelligent agents.
Compared with some of its major rivals, Apple has faced criticism for delivering standout AI‑based products.
The company has tried to add AI capabilities to its ecosystem through Apple Intelligence and the next generation of Siri, but the pace of its progress in this area remains one of the major questions about the company's future.
In fact, Cook's success in creating a very powerful services business has created a new challenge for his successor: how to bring that vast ecosystem into the AI era without eroding Apple's traditional advantages?
This issue is particularly important because AI can change how users use mobile phones, search, software and even personal devices.
John Ternus steps in at the most difficult time possible
Ternus takes the reins of Apple while the company remains one of the world's most valuable businesses, but the market expects the new CEO to find the next growth engine.
He has a long history at Apple and has for years been responsible for the hardware development of the company's products. His selection suggests Apple currently needs a leader who can put product development and innovation at the center.
Ternus's first major test is also very near. Apple is set to hold its product‑launch event on September 9; an event expected to introduce a new iPhone generation and possibly the company's first foldable iPhone.
According to AXIOS, this event will be the first major Apple product launch with Ternus as CEO.
Cook; CEO of a historic era
Despite all debates about the level of Apple's innovation during Cook's era, his financial record is hard to dispute.
He turned a company whose market value was about $347 billion when he began into a business worth about $4.7 trillion. Apple's shares also rose more than 22‑fold.
Of course, a direct comparison between Cook and Steve Jobs is not simple. Jobs played a very different role in Apple's history and his primary focus was on product, design and creating new categories of technology.
Even in terms of stock growth, Apple's performance during Jobs's era was higher in percentage terms.
But Cook's legacy should also be sought elsewhere: he managed to turn Apple after the Jobs era into a massive profit‑generating machine and put recurring services revenues at the heart of its business model.
Now that legacy is in John Ternus's hands; a manager who must not only preserve this $4.7 trillion empire but also shape Apple's response to the biggest technological transformation of recent years, namely artificial intelligence.