Amazon Kindles Lose Weight

The two six-inch-screen devices are smaller and lighter than Amazon's previous six-inch-screen Kindle, and they have more features.

The Kindle WiFi is priced at US$139, and the Kindle 3G + WiFi goes for $189. Both can be pre-ordered now and will ship Aug. 27, Amazon said.

More Pizzazz for Your Pesos

The two new devices are 21 percent smaller than the old Kindle, although they have the same six-inch screen size, Amazon said. They also offer 50 percent better screen contrast; crisper, darker fonts and a new Webkit-based browser.

With the new browser, Amazon has launched a beta program that gives owners of the new 3G + WiFi Kindle free 3G Web browsing.

Amazon has enhanced its PDF reader with dictionary look-up, notes and highlight capabilities. Further, page turns are reportedly 20 percent faster.

Owners of the 3G + WiFi Kindle get 3G wireless coverage in more than 100 countries and territories. The WiFi capability lets both new varieties of Kindle connect to hotspots at hotels and cafes. Connection to AT&T (NYSE: T) hotspots across the United States is free.

Amazon has doubled the storage for the new Kindles, and they can now store up to 3,500 books, just like the Kindle DX.