25th August 2011
He is to be replaced by its chief operating officer Tim Cook. Mr Jobs, who underwent a liver transplant following pancreatic cancer, said in a brief letter that he could no longer meet his chief executive's duties and expectations.
Apple shares slid more than 5% in after-hours trading. Some investors are less confident of the company's prospects without Mr Jobs at the helm.
But while there is already plenty of analysis of what now happens at Apple and whether the company can retain leadership of the world of technology – here are a range of views so far:
Rory Cellan-Jones, technology correspondent at the BBC, says: "Forceful bosses whose personalities shape everything about their businesses are going out of fashion these days, for good reason many would say.
"But Steve Jobs is a rare example of a chief executive who is synonymous with his company, a perfectionist who obsesses over every detail and has been the public face of just about every major product launch in the past decade.
"It's difficult to imagine Apple without him – but he's leaving having revived what was an ailing business when he returned in the late 1990s, and turned it into the world's wealthiest company and one which has done more than any other in recent years to shape consumer technology."
However, Shane Richmond, head of technology at the Daily Telegraph, says: "It would be foolish to believe that Apple is a one-man company, though the firm's desire to focus on its products and not its people means that Jobs's team is not terribly well known. One exception is Jonathan Ive, the British design guru behind some of Apple's best-known products, who has become relatively well-known.
"In fact, the unusual thing is that Jobs and Gates became household names at all. Most people outside the technology industry could not name the person in charge of Sony PlayStation or Amazon, despite the popularity of both brands."
The Guardian gives a range of views, including one by John Gruber, who says: "Apple's products are replete with Apple-like features and details, embedded in Apple-like apps, running on Apple-like devices, which come packaged in Apple-like boxes, are promoted in Apple-like ads, and sold in Apple-like stores. The company is a fractal design. … The same thought, care, and painstaking attention to detail that Steve Jobs brought to questions like "How should a computer work?", "How should a phone work?", "How should we buy music and apps in the digital age?" he also brought to the most important question: "How should a company that creates such things function?
"Jobs's greatest creation isn't any Apple product. It is Apple itself."
Meanwhile the Financial Times (paywall) says on its technology blog: "My first reaction to the resignation of Steve Jobs as its chief executive is sadness.
"Mr Jobs, at the age of only 56, stands as one of the great business leaders – arguably the greatest – of the postwar era. For the past 30 years, he has not only led the wave of technological change emanating from Silicon Valley – the personal computer, the internet, the tablet – but stamped his aesthetic on the world."
Stuart O'Gorman and Ian Warmerdam from Henderson comment on the perspective for investors: "The Henderson Technology team have long been advocates of Apple having bought into Apple way back when the iPod was a mere twinkle in Jobs' eye and shares were changing hands for $10.
"There's no doubt the influence of Jobs has been hugely important in making Apple the company it is today. However, we believe Apple will continue its onward march not least because the market has been well aware of Jobs health issues and there is certainly no ‘Jobs premium' built into Apple's valuation. Let's not forget he will continue to play an important guiding role as Chairman. Apple trades on forward PE of 11x which is only a small premium to the market. If you give some value to their huge cash pile on the balance sheet then it looks even more attractive, trading at a PE of 8.5x 2012 ex cash. This is cheaper than the market, cheaper than the Technology sector for a company that is exceptionally well positioned and grew revenues over 80% (year over year) last quarter!"
Reuters' analysis says that the resignation of Steve Jobs has opened the door for rival Samsung Electronics at a crucial time in the battle for smartphone supremacy in salesrooms and courtrooms around the world.
The Register says: "Today's Apple is Steve Jobs' Apple – staffed by Jobs, steered by Jobs, focused by Jobs, and given its marching orders for well into the future by Jobs. And if you don't believe that, you don't know Jobs.
"From the inception of Apple Computer, Jobs has repeatedly demonstrated that success is his prime directive. If someone got in his way – even cofounder Steve Wozniak in a well-documented 1985 run-in over the Apple II – Jobs took no prisoners."
You can find a collection of the best Steve Jobs quotes here from the Wall Street Journal.
For Steve Jobs career in pictures, visit this BBC page.
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