Today's Free App of the Day is ZDefense
This is a tower defense game based on a hexagonal grid. It's got great reviews, however, the twenty one-star reviews complain about the permissions required (account information) and that the game is a rip off of another game.
119 of 169 reviews are four stars and above.
These apps are compatible with the original Fire and with my Fire HD 8.9" 4G. To tell if an app works for your Fire HD or other Android device registered to your Amazon account, click on the above link and look on the right side of the web page. Amazon will tell you if it will work with your registered device.
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