The phrase "extra gig" means an additional job or task that someone does, usually to earn more money or gain more experience, on top of their regular job or responsibilities. Full definition
Basically, the Galaxy Note 8 is an ever so slightly larger derivation of the GS8 +, with twice the rear - facing cameras in tow, a couple of extra gigs of RAM, and believe it or not, a smaller battery keeping the 6.3 - inch «Infinity Display» lights on. (pocketnow.com)
A need is generally considered food, shelter, and clothing; extra gigs on your phone, dining out, MEC's coolest gear, and the latest runway looks don't count. (creditcanada.com)
We know all the specs, including the recently announced extra gig added to the 8 that was announced purely for gaming development, but what we want to know is what does it look like, when is it coming and probably the most important question is what is it going to cost? (gameondaily.com)