An Apple employee points to the new cylindrical Mac Pro. Photo: AFP
It will be released later this year and be assembled in the United States, Schiller said.
Apple's stock has fallen 37 per cent after touching a high of $US705 in September as competition in the key smartphone market escalated. Some investors believe the company that invented the iPhone is struggling to come up with original new products after co-founder and former CEO Steve Jobs died in 2011.
"Can't innovate any more, my ass," Schiller said as he showed off the new Mac Pro. "This is a machine unlike anything we've ever made."
Apple also announced a new operating system for the Mac PC called "Mavericks," moving away from its penchant for naming its computer software after big cats. The new OS can handle multiple display and "tagging" of documents, among other new features.
In an unusual move, Apple also shared the stage with little-known startup Anki, which was given the opportunity to show off a game.
The conference, whose tickets sold out in just over a minute when it opened up in April, comes as South Korean rival Samsung has solidified its lead in the smartphone market with a 33 per cent share followed by Apple with 18 per cent during the first quarter, according to market research firm IDC.
Cook is under pressure to show that the company that created the smartphone and tablet markets is not slowing down as deep-pocketed competitors such as Samsung and Google encroach on its share.
Investor concerns centre around whether Apple will be able to come up with more groundbreaking products as smartphone and tablet market gets more crowded.
In April, Apple reported its first quarterly profit decline in over a decade.
Cook told the audience of developers at the Moscone Centre in San Francisco that Apple's App Store now has 900,000 apps, which have been downloaded a total of 50 billion times.
Apple's stock fell 0.66 per cent to close at $US438.89 on Nasdaq.
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