The Element Fire TV Edition televisions have a full-sized SD card slot, as well as a pair of USB ports, where one is USB 2.0 and the other is USB 3.0 speeds. It was expected that only the SD card slot would be used for external app storage, since that’s the way the Fire TV 2 works with its microSD card slot. I can confirm that only the SD card slot on the television is available for external app storage. The television does recognize when you connect USB drives, but warns you that they cannot be used to store apps, like the Fire TV 1 can do. Files can be accessed through either the SD card or a USB drive via 3rd-party apps, like media players (e.g., Kodi, MrMC, SPMC, VLC, etc..) or file managers, but only the former can store apps to augment the Fire TV Edition televisions 16GB of internal storage.