Amazon on Thursday further bolstered the defenses of its popular Kindle electronic readers in apparent anticipation of Apple unveiling a hot new tablet computer next week.
A day after pumping up the royalties it pays to authors or publishers who offer digitized books for sale to Kindle users, Amazon invited software savants to craft fun, functional or hip programs for the e-readers.
"We've heard from lots of developers over the past two years who are excited to build on top of Kindle," Amazon Kindle vice president Ian Freed said while announcing the pending release of a kit for building programs for the devices.
"The Kindle Development Kit opens many possibilities -- we look forward to being surprised by what developers invent."
An interactive Zagat guide is in the works to wirelessly deliver updated restaurant reviews and ratings to Kindles. Sonic Boom is crafting word games and puzzles for Amazon e-readers.
"We look forward to bringing some of the world's most popular and fun games to Kindle and their users, said Adam Sussman, vice president of worldwide publishing at the mobile division of US videogame titan Electronic Arts.
Applications made by outside developers should be on the virtual shelves of the online Kindle Store later this year, according to Amazon.
Developers can learn more about the development kit at a website at www.amazon.com/kdk/ and sign up to be notified when a limited testing phase starts next month.
Amazon on Wednesday unveiled a higher royalty payment scheme for authors and publishers who use a self-publishing platform on its Kindle platform.
The online retail giant said the new royalty option will allow authors to keep 70 percent of the list price of a digital book minus delivery costs, which work out to around six cents per unit.
Amazon did not reveal the amount of the previous standard royalty option.
Amazon said the new 70-percent option will be available from June 30 and comes with a number of conditions.
The list price of a digital book must be between 2.99 dollars and 9.99 dollars and 20 percent below the lowest list price for the physical book.
Seattle-based Amazon said the 70-percent royalty option only applies to in-copyright works and, for the moment, is only be available for books sold in the United States.
Amazon's moves come less than a week ahead of a hotly anticipated product announcement by Apple, which is widely expected to unveil a tablet computer which can double as an electronic reader on January 27.
"They are battening down the hatches and getting ready for war," Silicon Valley analyst Rob Enderle of Enderle Group said of Amazon bracing for Apple launching a tablet-size version of its iPod Touch device.
According to various reports, Apple has been holding talks with book, newspaper and magazine publishers about making their content available for the device.
"Apple is clearly moving into areas that Amazon thinks of as its own. Amazon has to move into apps much like Apple is moving into their space," Enderle said.
"Amazon is aggressively moving against the iTablet, iSlate, or whatever Apple's device is going to be called."
Amazon is expected to upgrade its Kindle line, adding color screen and multimedia capabilities along the lines of features expected in an Apple tablet.
Amazon's Kindle is considered the runaway leader in the e-book reader field but has been facing increasing competition from Japan's Sony, Britain's Cool-er and US bookstore Barnes and Noble among others.
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