Amazon Kindle boosts battery life, adds PDF reader

To compete with the Nook, the Amazon Kindle patches some holes in its feature list.

As shoppers draft their holiday wish lists, Amazon made a move today to nudge potential e-reader buyers into asking Santa for a Kindle.

A free software update will now patch up one of the frustrating holes in Kindle's feature list and increase its battery life.

The e-readers can now get up to a week of power when its wireless antenna is turned on. Before, Kindles lasted about four days. This update makes the wireless features more energy efficient, so there is not a similar boost in the two-week battery life enjoyed when the connection is turned off. Kindle's chief competitor, the Barnes and Noble Nook, will run for 10 days with wireless functions disabled.

Amazon also added PDF support. Earlier firmware required Kindle owners to convert PDF files into a proprietary format – where as the Nook, Sony Reader, and the larger Kindle DX could display PDFs without a hitch. This helps ease comparisons between the three leading devices. But Kindle still does not recognize ePub files, which Google uses for its half-million public domain books.

The Kindle must feel some heat from Barnes and Noble's announcement this week that the Nook has sold out until 2010. However, much like Amazon, B&N did not release any numbers to reveal whether selling out is an impressive feat or not. Our only hint is Forrester Research, which predicts that the e-reader market will sell 3 million devices in 2009 and could double next year.

Looking for more information on which e-reader is for you? Check out our coverage and reviews:

Barnes and Noble Nook gets a reception fit for a king

Sony Reader v. Amazon Kindle: the next round

Review roundup: Amazon Kindle 2

Review roundup: Kindle on the iPhone

Introducing the super-sized Kindle DX

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