I'd like to make sure I have the latest firmware for my Lumix GX1 (and soon getting a GX7), but I'm not sure how to check the installed version or how to find what the latest is.
According to the manual(pdf), page 59 it can be shown with the [VERSION DISP.]
option from the Setup menu.
The latest version of all body and lens firmwares can be found on Panasonic's Joint update service for Four Thirds lenses page.
firmware
on page 37. It is found in the Setup menu. I've downvoted for lack of research effort for now. If the manual is not sufficient in finding the firmware version please edit your question explaining what you have attempted. – Saaru Lindestøkke Apr 28 '14 at 16:20