When selecting USB devices to use on the EPIC groov, what O/S compatibility shoud I look for?

The question pretty much says it all – does the EPIC groov support any USB device that claims it has Linux driver support, or are there limitations.

In general, how do I tell whether or not I can use a given USB device with the EPIC groov?

As per the manual, only 2 listed USB to serial converters, 3 listed Wifi adapters, Keyboard and Mice are supported at time time.

What devices are you looking for / thinking of?

Right now, we need to add 4 RS-232 ports.

Yep, not a problem.
Page 42 of the manual;