TIP

It is actually possible to work around the limitation of only being able to read books you have downloaded from Amazon, but it takes some work. Obviously, you should not take this as a license to download books illegally, but there are nonetheless times when you may have a book you acquired legitimately through another source. For example, as the author of the Adobe Flash Catalyst CS5 Bible, I was able to get an electronic copy of it directly from the publisher, but as I had not downloaded it from Amazon, the Kindle app was not willing to open it. After doing some digging online, I discovered that the app, quite obviously, only syncs with Amazon's server when it is online. Therefore, you can copy a book you did not download into the Kindle's directory, then turn off both Wi-Fi and 3G, launch the app and read the book successfully. The easiest way to disable Wi-Fi and 3G, by the way, is to turn on Airplane mode. You just need to be sure to move the book's file back out of the Kindle's directory before you go back online.