Apple today is nearly a $1 trillion dollar company and despite the global slowdown, has been able to not only maintain its growth trajectory but also diversified into services, entertainment and other verticals which are bringing in more moolah than its devices segment.
Cook has spent over two decades at Apple, and nine years as CEO, and people across the globe now have a valid question: who is Apple's best bet to replace Cook as CEO and keep the company on the growth path?
For Jobs, Cook was the natural choice and he picked him over more popular names around for the CEO job, like legendary Apple Chief Designer Jony Ive (who has now moved on).
Cook became COO in 2005, and officially Jobs' right hand man. Identifying his unique set of strengths, Jobs made him the Apple CEO on August 24, 2011.
In December 2015, Cook promoted his long-time lieutenant in operation - Jeff Williams - to the role of Apple COO. The duo later created history.
Williams has been called "Tim Cook's Tim Cook". He is in charge of the operations side of the business, just as Cook used to head up operations when Jobs was CEO.
"There are uncanny number of similarities between Williams and Cook," writes journalist Leander Kahney in his biography of Tim Cook.
According to Fortune reporter Adam Lashinsky, "Williams is in many ways a doppelganger for Cook".
"Tall, lean, and grey-haired, like Cook, Williams was said by Apple executives to look so much like his boss that from behind, they could be mistaken for each other," writes Lashinsky in his book "Inside Apple".
Since 2010, Williams has overseen Apple's entire supply chain, service and support and social responsibility initiatives the "last being something that has grown in importance under Cook".
According to Kahney, Williams has been instrumental in speeding up the iPod delivery process, making it possible for customers to buy an iPod online, have it custom engraved, and delivered in three working days.
He is also said to be a key contact with supplier Foxconn.
According to Apple analyst Neil Cybart, "Williams is tasked with making sure the Apple machine is well-oiled and in tip-top shape, not only capable of producing more than 100 million iOS devices in a quarter, but building flexibility into the system to handle annual hardware updates that would make most hardware companies quiver with fear."
Williams played an important role in the development of the first-generation iPhone, and has since led worldwide operations for both iPhone and iPod. Today, he also supervises development for Apple Watch.
Often called the "unsung hero", he led the development of Apple Watch in close collaboration with the design team, and oversees the engineering teams responsible for Apple Watch.
According to Apple, he is also driving the company's health initiatives, pioneering new technologies and advancing medical research to empower people to better understand and manage their health and fitness.
Williams joined Apple in 1998 the year Cook joined the company as head of Worldwide Procurement.
Prior to Apple, he worked for the IBM Corporation Cook also worked with IBM before joining Apple from 1985 to 1998 in a number of operations and engineering roles.
Like Jobs, the passing on the Apple baton to Williams is a natural choice for Cook too.
Cook is still going strong and Apple, under his watch, is breaking all sorts of records.
With Jobs' 'spiritual partner' Sir Jony Ive now out of Apple, Williams is without doubt Apple's best bet to take over when Cook finally decides to move on.
(Nishant Arora can be reached at nishant.@.in)
( With inputs from IANS )