ENGLEWOOD, Colo.--(BUSINESS WIRE)--Sling TV released its app for Amazon Fire HD and HDX tablets, rounding out its live Internet TV offering on Fire devices, including Amazon Fire TV and Fire TV Stick. Amazon Fire HD and HDX tablet device owners can now download the Sling TV app in the Amazon Appstore. For a limited time, new Sling TV customers with an Amazon Fire HDX 8.9, Fire HDX 7, Fire HD 7 or Fire HD 6 tablet can also take advantage of a 14-day free trial of Sling TV. “Amazon customers now