I was able to buy a copy, but I could not through kindle phone app. I had to use the web site. I was getting a 404 error for foxprints. the site seems to be up now. :) Kindle said it was a permission issue & they will contact you. Theta did not come up in search in the app on my phone. Might be different on the actual device. Those apps tend to be buggy but the tech on the phone had the same problem finding Theta. ?