Amazon has free Kindle apps for a wide variety of platforms. Once you've installed the correct app for your device, you register it to your Amazon account and all of your Kindle books will be available for download. Here's the link to Kindle apps:
http://www.amazon.com/gp/feature.htm...cId=1000493771
In general, you can't read Kindle books on non-Kindle e-ink devices because most don't support apps and don't support the Kindle format, unless you convert them to a supported format.