I have an unmodified Zeki TB782b (no Google Play store). As reported earlier, I updated Amazon's Appstore and got a nice grey screen for my efforts. Another user reported Amazon promised a fix, and so I waited, usin v. 2.6 as I said. Nobody got back here and reported the fix. I got tired of waiting & tried the update this morning, and apparently it works now. I'm running v. 4.5.16. ... now. Happy apping!