I downloaded a mobi format book using my galxy 7 plus. When I click on the "downloaded" file it says I can't open it. The galaxy has the installed Kindle Bookstore ap so I assumed I could read mobi books. Do I need to install another reader? If so, which one is recommended. I also downloaded the same book in epub format and when I clicked on the "downloaded" file the book went to my ebook file and I could read it. Do I have to download only from amazon using the kindle ap to read mobi formatted books with the original tablet setup? I want to download this particular book in all formats possible because it is one that I wrote and I want to view it in all formats on my tablet........thanks!