The description of the Hub says it can be used with other devices when your computer is powered down. Does this indicate that is completely free-standing and can be used without ever being connected to a computer? Can you take it somewhere and connect it with HDMI or other connections to a TV and play content? Can you upload files to it from a camera or camcorder, with no computer required?
As long as the Camera / Camcorder looks like a USB device, yes, you can play or copy the files.
Yes, you can make it stand alone without any attachment to ANYTHING, but some things won’t work correctly (the weather icons / clock, etc, get their information from the internet, so if that’s not available, they won’t be correct.)