Starting January 28th, Foursquare will divulge more of your private information to complete strangers. Businesses you visit will have greater access to the record of your visit. If that freaks you out, it’s time to lockdown your privacy. You can change your full name to whatever you want, or block strangers from seeing your check-ins. Never post anything to a social network you wouldn’t want the whole world to see, just block them from seeing you at all.”]
Source: https://gizmodo.com/how-to-protect-your-privacy-on-foursquare-5972886