Sorry if this was answered already.
Is there a way I can hook my phone or tablet up to my TV to watch Youtube videos? My STB has a USB port on it but I'm not sure what it's for.
Is there a way to hook my device up to the TV?
Only if you have connections directly from device to TV.
STB does not provide pass through capability.
TheVMS/IP boxes already do Youtube. Its a possible future option for the VMS stb to stream some channels to your devices and perhaps vice versa.
Older Verizon boxes used to do youtube by talking to software on your PC. Not sure if they still will if you have the software still installed, as the software was retired.
And of course some TV's have options to talk to smartphones.