Amazon founder and CEO Jeff Bezos showed off the Kindle Fire today, a $199 tablet computer, challenging Apple’s iPad by extending its Kindle brand into the world of full-color, multipurpose devices.

Bezos also took the opportunity to unveil a new line of Kindle e-readers with black-and-white screens and lower prices, further pressuring competitors like Barnes & Noble Inc. that are trying to break Amazon.com Inc.’s dominance in electronic book sales.

The Kindle Fire will go on sale Nov. 15. It’s about half the size of the iPad, making it a close match with Barnes & Nobles Nook Color tablet, which came out last year. But while Barnes & Noble sees the Nook Color as jazzed-up e-reader, Amazon has broader goals for the Fire, as a platform for games, movies, music and other applications.

The Fire runs a version of Google Inc.’s Android software, used by other iPad wannabes, and will have access to applications through Amazon’s Android store. Unlike the iPad, the Fire doesn’t need to be backed up on a PC. Instead, it backs up its contents wirelessly on Amazon’s servers.

“That model that you have to back up your own content is a broken model. We want to take responsibility for that,” Bezos said in a dig at Apple. He was speaking at a press event in New York.

The cheapest new Kindle will cost $79, and dispenses with the keyboard the Kindles have carried since the first model launched in 2007. Previously, the cheapest Kindle cost $114.

Amazon is also bringing out the first black-and-white Kindle with a touch screen. It will cost $99 and is reminiscent of Barnes & Noble’s latest Nook. A version with access to AT&T’s cellular network for book downloads will cost $149.