I purchased the premium account of the app. But in Amazon fire tablet, it's asking purchase the premium again. That's not fair to charge for each OS seperately. In my Android TV it's working fine. Response to the developer who responded: I know the platforms are different, may not be as knowledgeble as you( are. But thanks for all the gnan you had given. One thing you should understand is, the customer and the seller(development company) and the app are same. But looting is twice.