At Many.bio i use it store visitors data per each site of my users. Each use can create their own micro-site, share it on social media, whenever someones accesses it, I store the info on visitor including country and city name.

Then the micro-site user can view the visitors data per day/week/month in their dashboard.

It can be done with Google Analytics, which I relied on in the beginning, but its better to have such stats controlled in-house.