Amazon bolsters battery life for Kindle; Adds native PDF reader

Amazon on Tuesday said it has improved the battery life of the Kindle and added a native PDF reader.

The statement appears to be timed to get holiday shoppers off the fence about the Kindle as rivals like Barnes & Noble and Sony struggle to meet demand in time for Christmas.

Specifically, Amazon said it improved the Kindle battery life by 85 percent. In real world terms, that battery life equates to up to seven days with wireless turned on. Kindle said the improvement was delivered during a six month firmware improvement program.

The PDF reader means that Kindle users don't have to convert documents in the PDF format. Kindle users can transfer the PDF documents via email or USB.

And naturally, Amazon noted that the Kindle is in stock.