Something that greatly differentiates the Fire TV Cube from the Fire TV 3 is the Cube's Micro USB port and the official support for expandability that comes with it.
Why you should buy a Fire TV Cube over a Fire TV Stick
Ethernet Adapter for fire Stick TV Cube, Google
Everything you can do with the Fire TV Cube's Micro USB
Everything you can do with the Fire TV Cube's Micro USB
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The different Micro USB OTG Adapters and Accessories that work
Ethernet Adapter for Fire TV Stick, Electop Micro USB
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Ethernet Adapter for fire Stick TV Cube, Google
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