Apple CEO Tim Cook introduced the new iPad Air Tuesday. Associated Press
SAN FRANCISCO— Apple Inc. AAPL +0.11% introduced two new iPads to bolster the company's position in an increasingly competitive tablet-computer market.

Apple's Event

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Apple CEO Tim Cook kicked off Tuesday's event in San Francisco with an update on recent performance. Apple held its second gathering in as many months on Tuesday, making good on its usual fall event to showcase new products ahead of the holiday. REUTERS
At an event here Tuesday, Apple revealed an updated iPad Mini, with a faster processor and a sharper display. Apple also showed off a new full-size tablet—called iPad Air—that is thinner and lighter.
Among other announcements, Apple said a new version of its computer operating system, OS X Mavericks, along with updates to 20 more of its apps, would be available for existing customers to download free immediately, a shift from the company's past practice of charging for software updates.
The new iPads will be priced at $399 for a 16-gigabyte Mini model and $499 for a 16-gigabyte Air. An earlier version of the iPad Mini without the sharper screen, will sell for $299, a new low price for the company's tablet lineup.

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Phil Schiller, head of the company's marketing efforts, said Apple has been "on a relentless path" updating its iPads each year. "iPad is delivering a new vision for mobile computing."
The new iPad Air—which is 20% thinner and weighs 1 pound, down from 1.4 pounds—goes on sale in the U.S. and a host of other countries, including China, on Nov. 1. The new iPad Mini will go on sale later in November, the company said.
"I can't think of another product that's come so far, so fast," Chief Executive Tim Cooksaid, noting that Apple has sold more than 170 million iPads.
With the free software approach, "we are turning the industry on its ear," Mr. Cook said.
Apple also unveiled a slate of new computers: Its latest MacBook Pro laptop computers will start at a price of $1,299, about $200 less than past models, while its high-end Mac Pro desktop computer will start at $2,999.

More From Digits

The main news, though, were the new tablets, which come at a critical time for the Cupertino, Calif., tech giant. For the first time, Apple sold fewer iPads in the three months ended in June than the same period a year earlier. Rivals including South Korea's Samsung Electronics Co.005930.SE -0.61% and Amazon.com Inc.AMZN +0.10% are eroding Apple's one-time dominance of the tablet market.
Research firm Gartner expects Apple's share of the tablet market to fall below 50% this year, down from 54% last year and 65% in 2011. Tablets powered by Google Inc.GOOG -0.06% 's Android operating system are expected to hit as much as 50% of the market this year, up from about 45% last year.
As evidence of the intensified competition, Nokia Corp. NOK +2.80% unveiled its first tablet computer Tuesday. Also Tuesday, Microsoft Corp. MSFT -1.17% , which plans to acquire Nokia's mobile-computing business, put the second version of its Surface tablet on sale.
Google, Sony Corp. 6758.TO +0.73% and Asian manufacturers including Asustek Computer Inc. 2357.TW +2.98% and Lenovo Group Ltd. 0992.HK +0.98% are pushing tablets of their own.
Even as Apple loses market share, its customers remain the heaviest users of tablets. Mobile-advertising firm Chitika Inc. says 84.3% of the website traffic from tablets that it analyzed in June came from iPads. Amazon's Kindle Fire tablet ranked second, with 5.7% of Web traffic, followed by Samsung's "Galaxy" tablets, with 4.2%. Usage of the iPad increased from May to June, Chitika said, while the others declined.
"Regardless of what you might hear or read about how many are sold or activated, iPad is used more than any of the rest," Mr. Cook said, adding that the iPad is used four times more than competitors.
At its event, Apple also gave a few updates on the rollout of products it introduced in September. Mr. Cook said that as of Tuesday, 64% of Apple's mobile devices run its latest operating system, iOS 7. "This blows away the other guys," he said.
Apple also said that developers in the company's App Store have earned more than $13 billion since the App Store opened. The company said in January that amount was at about $7 billion.
Write to Ian Sherr at ian.sherr@wsj.com and Greg Bensinger atgreg.bensinger@wsj.com