The answer to this question is not as puzzling as it might first seem, because the answer is very straightforward – when it’s an App.
Basically once you have bought a Kindle book you don’t actually need a Kindle to read it. The Kindle app is available for every type of tablet, smartphone or computer and you can download the one you need here at Free Kindle Apps
If you have a Kindle then that is fine because you can of course read Kindle books on any of the Kindle devices including the Kindle Touch and the Kindle Fire. This will also give you access to the special functionality the Kindle offers. Features like synchronizing the furthest page read, bookmarking, making notes and highlighting across all your different devices. This is done using Amazon’s Whispersync app which was developed so that, no matter what device you choose to read your book with at any time, they will all be up to date and will remember where you were in your book so you can continue where you left off seamlessly. You don’t even need to own a Kindle to useWhispersync, you can use it for your other devices.
A nice feature of a properly formatted Kindle book is the ease with which you can change the font size to suit you and your eyesight. This makes the process of reading your book so much more rewarding, especially when using the E Ink display which I think most people are aware of, if only because of the facility it provides for reading in bright sunlight whilst remaining very clear and crisp. What some people may not be aware of is that you can also change the Typeface, Line Spacing, Words per line and screen rotation very easily and simply. So your reading experience with a Kindle is truly enhanced by letting you choose exactly how you want to read it. A paper book simply can’t do that, but if you feel that you like the way a paper book sits in your hand, you might like to consider buying a cover for your Kindle, then when you flap open the cover to start reading it looks and feels much more like a traditional paper book.
Don’t forget that you are also allowed to read the first chapter of any Kindle book before you have to decide if you want to buy it and usually the ‘Look Inside’ feature is available on Amazon for taking a peak at a book even before you need to download the book or the sample pages.
So yes your Kindle books can be read on your Kindle, BlackBerry, Android devices, iPhone, iPad, Windows Phone 7, Mac, PC, or web browser, my personal preference is the most basic Kindle, which also happens to be the cheapest.