Apple Inc. debuted an eight-inch iPad Mini on Tuesday to compete with an increasingly crowded small-tablet market, currently dominated by Amazon鈥檚 e-readers.

The Mini is ultra-thin and weighs much less than the iPad. Its screen is also two-thirds smaller. Apple has also upgraded the full-sized iPad, doubling the speed of its processor, adding a better camera and replacing the 30-pin dock connector with a smaller "Lightning" connector introduced with the iPhone 5 a month ago.

The iPad Minis will retail for US$329 and customers can begin ordering them on Friday. Industry observers had expected Apple to price the Mini at $250 to $300 to compete with Amazon鈥檚 Kindle Fire, which starts at $159. Barnes & Noble Inc.'s Nook HD and Google Inc.'s Nexus 7 both start at $199.

The iPad Mini will also compete with the release of Windows 8, Microsoft鈥檚 new operating system.

The gadget has a 7.9-inch screen on the diagonal and two cameras, one on the front and one on the back. The screen resolution is 1024 by 768 pixels, the same as the iPad 2. That鈥檚 slightly larger than Google鈥檚 7-inch Nexus 7.

The new model has better apps and is easier to use than competitors like Google's Nexus, Avi Greengart, a consumer electronics analyst with Current Analysis, told The Associated Press.

"This really is not in the same category as some of the other 7-inch tablets," he said. "And that's before you consider that it has a premium design -- it's made of metal that's extremely lightweight."

At the Apple event Tuesday, the keynote presentation included an example of how 麻豆影视 uses the Streambox app, which allows reporters to stream live video from their locations to broadcast on air.

The late Steve Jobs, Apple鈥檚 founder, once famously mocked the seven-inch tablet, saying it was too big to compete with smartphones and too small to compete with other tablets. But Apple鈥檚 senior vice-president Eddy Cue said an email sent to other Apple managers in January 2011 that Jobs had started warming to the idea. Jobs died about nine months later.

Tech analyst Carmi Levy said the iPad Mini could become more popular than the iPad because it will attract consumers who stayed away from the more expensive full-sized tablet.

鈥淛ust by virtue of economics, I think these things are going to sell absolutely huge,鈥 he told 麻豆影视 Channel Tuesday.

Levy also said Apple can charge more for its small tablet because of the features it offers.

鈥淭he difference is, when you buy an Apple device, you鈥檙e not just buying the hardware, you鈥檙e also buying iTunes, you鈥檙e buying that whole ecosystem that none of the other devices have,鈥 he said.

But some analysts have concerns about the iPad Mini, saying its higher than expected price may not give it a competitive edge in the smaller tablet market. 

Apple shares fell $20.67, or 3.3 per cent, to $613.36 when the price was announced. Shares of Barnes & Noble Inc. jumped 88 cents, or 6.1 per cent, to $15.32. Shares of Amazon.com Inc. rose 53 cents, or 0.2 per cent, to $234.31.

Apple has sold more than 100 million iPads since April 2010.

With files from The Associated Press