Amazon and Barnes & Noble have been quietly expanding the number of free apps available to read Kindle and Nook eBooks on any tablet, smart phone or computer.

Free Kindle and Nook apps are now available for PC, Mac, iPad, iPhone and Android devices. Kindle also has a free app for the BlackBerry, as well as a Cloud Reader that makes it possible to read a Kindle eBook in any browser on any computer, tablet or smart phone.

Until this week, one had to go to separate Amazon and Barnes & Noble websites to find all those free eBook reading apps. Now one website provides links to all those free apps in one place.

LifeWithSiri.com has been completely redesigned and was relaunched today with links to all the free eBook reading apps on its home page. The new LifeWithSiri.com website also provides comprehensive information about how to use Siri, the voice-recognizing “personal assistant” on the iPhone 4S. Its home page has been redesigned to include links to 9 eBooks about Siri, more than 40 articles and 20 videos about Siri and a sample preview of the largest of its 3 “Life With Siri” eBooks.

While nearly all other eBooks are mainly text-based, “Life With Siri” primarily uses iPhone screenshots to demonstrate how to most effectively utilize Siri. In its new 2nd Edition, there are more than 100 screenshots. Author Jodi Dery states, “I believe that presenting Siri’s responses in this illustrative manner — with maximum use of screenshots and no more text than necessary — will help people remember the best way to talk to Siri and get the results they want.”

The “Life With Siri” eBooks range in price from $.99 to $1.99 and are available from both Amazon and Barnes & Noble.