The micros USB port on the back of the Fire TV Cube will most commonly be used to connect the Ethernet Adapter that comes included in the box with every Fire TV Cube, but with the right adapters or accessories, it can be used for so much more, as is described in this article.
Everything you can do with the Fire TV Cube's Micro USB port — Ethernet, App Storage, External Drives, Peripherals, FLIRC, OTG, and more
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The different Micro USB OTG Adapters and Accessories that work well with the Fire TV Cube
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