Looking at my traffic via the Unifi desktop, my #1 categorized type of mystery connection is "Google App Engine (SSL)" and those connections are solely from the Mac that runs my Indigo setup.
I use no Google services directly, never visit google.com, am not logged in to Google anywhere, and have no Google apps installed. The ONLY thing that maybe touches google that I know of is FindFriendsMini, which gets URLs for location of the two users of Indigo.
Does Indigo itself make any calls to Google? It's not a LOT of data, ranked as <0.1%" by Unifi. Mostly I'm just curious if anyone has an idea. I do use this machine for some web browsing on occasion, and suppose it could be various site trackers reporting back to the all seeing corporate headquarters.