Do what I do.
PURCHASE so you legally own the book, use various process to remove DRM (PM me if you need help with that....VERY SIMPLE with kindle and a PC) then convert to EPUB via Calibri. Then use a variety of readers available for android...I prefer Aldiko.
This has 1 more advantage....you can purchase books from a variety of sources and with a little work convert them and use a single reader, instead of having one for Kindle, one for Nook, one for Boarders, etc on your phone.
A non-DRMed book modified with Calibri has one other advantage....you can add any cover you want. For some reason a LOT of US books that are international sellers get crappy covers. If you need an example, just look at the original hard back covers for the Harry Potter series and compare to the UK versions. From what I have read, American publishers require "bright" and "LOUD" covers where as other countries apparently have more sophisticated readers that are able to find books to read without dumbed down covers.