The announcement strengthens the bid by Amazon for control of the e-book market and the devices consumers use to read them.
Amazon hopes that the Kindle becomes the iPod of the literary world, challenging the printed book.
Perhaps most significantly, Amazon said it would start selling e-books that can be read on mobile phones and other devices, although Amazon did not say when it would do so or which devices would be compatible.
The Kindle 2 has several incremental improvements over its predecessor, which went on sale in 2007. Amazon said the upgraded device has seven times the memory of the original version, turns pages faster and has a sharper display.
It also features a new design with round keys and a short, joysticklike controller — a departure from the earlier design, which some buyers had criticized as awkward. The device will ship Feb. 24. The price remains at $359.
For $3.99, all Kindle users can buy a short story by Stephen King that will be exclusive to the Kindle for a limited time.
“Our vision is every book, ever printed, in any language, all available in less than 60 seconds,” said Jeffrey P. Bezos, Amazon’s founder and chief executive.
Amazon also announced a new feature, Whispersync, which would allow readers to begin a book on one Kindle and continue, at the same point in the text, on another Kindle or a mobile phone.
Analysts say the move is aimed at establishing Amazon as the dominant e-commerce platform for books, a position similar to the one Apple has assumed in music with its iTunes Store.
“For the Kindle format to really take off, it has to go beyond being a very expensive device that has broad but still limited appeal and be able to get the content onto other devices like the iPhone,” said Michael Gartenberg, an analyst at Interpret, a market research firm.
Amazon faces a serious challenge from Google, which has scanned some seven million books, many of them out of print. Google said last week that it would soon sell books from its publishing partners for reading on mobile devices like the iPhone from Apple and phones running Google’s Android operating system.
Addressing Google’s initiatives, Mr. Bezos said in an interview that Amazon knows what book buyers want and stressed the company’s digital catalog of 230,000 newer books and best sellers.
“We have tens of millions of customers buying books from us every day, and we know what it is that people want to read,” Mr. Bezos said.
Apple poses another potential threat to Amazon’s plans. Several companies have created e-book programs for Apple’s iPhone and iPod Touch, which have been downloaded more than a million times.
Mr. Bezos said that reading on these kinds of gadgets might be fine when waiting in line in the supermarket, but that most people would want a dedicated device with a specialized screen for reading.
“If you are going to read for a couple of hours, you are going to have problems with battery life with a mobile phone, you are going to have eye strain and you are going to have problems with screen size,” he said. “Reading is an important activity and deserves a purpose-built device.”
For publishers, Amazon’s e-book efforts could represent a bright future, as the book industry struggles to sell traditional formats. But some worry that Amazon may be assuming too much control over pricing, similar to the influence Apple has established in the music business.
Amazon generally charges $9.99 for the digital versions of best sellers, although many publishers still sell the digital content to Amazon for the same price that they sell physical books. That means that for now, Amazon is taking a loss or making a small margin on the sale of some e-books.
“We do not agree with their pricing strategy,” said Carolyn K. Reidy, chief executive of Simon & Schuster. “I don’t believe that a new book by an author should ipso facto be less expensive electronically than it is in paper format.”
Mr. Bezos disagreed. “E-books should be cheaper than physical books. Readers are going to demand that, and they are right because there are so many supply chain efficiencies relative to printing a paper book,” he said.
Paul Aiken, the executive director of the Authors Guild, said that at some point Amazon was likely to put pressure on publishers and authors rather than raise consumer prices.
“The thought that there might be one very dominant player who could squeeze most of the profits out of this new market is frightening for authors and publishers,” Mr. Aiken said.
Richard Sarnoff, president of Bertelsmann Digital Media Investments, a unit of Bertelsmann, which owns Random House and is the world’s largest publisher of consumer titles, said that for this reason, publishers have remained vigilant in fostering competition in the e-book market.
“The key thing for us as publishers and our authors is that the value to a consumer of the underlying content is not undermined by artificially low pricing policies that end up sticking,” he said.