Much of the time I download the ebooks I read from the Amazon Kindle Store.
I use the basic, cheapest Kindle which only weighs six ounces and is ideal for a bed-time read.
Recently I bought an iPad mini and I've put the Kindle app on it so I can read on that as well.
The app works just as well as the Kindle; in fact the search facility is much better with the touch screen.
So, if you want to read Kindle books but don't want the expense of buying a Kindle, just go to this page on the Amazon site and download the free app for your preferred device. As well as iPad there's an app for laptop, P.C., phone, tablet etc. Just follow this link to the Kindle Store and start reading some fantastic indie published ebooks at very reasonable prices.