Foursquare vs Google Plus

Foursquare is a location-based social networking website for mobile devices, such as smartphones. Users "check in" at venues using a mobile website, text messaging or a device-specific application by selecting from a list of venues the application locates nearby. Location is based on GPS hardware in the mobile device or network location provided by the application, and the map is based on data from the OpenStreetMap project. Each check-in awards the user points and sometimes "badges". The user who checks in the most often to a venue becomes the "mayor," and users regularly vie for "mayorships."
Google Plus
Google+ (Google Plus) is a social networking and identity service. It's as a "social layer" that enhances many of Google online properties, and that it is not simply a social networking website, but also an authorship tool that associates web-content directly with its owner/author. Google+ users are interacting socially with Google+'s enhanced properties, like Gmail, +1 button, and YouTube comments.
Face to face in the news:

2016 - Foursquare will allow businesses to know if their ads bring customers into actual store to challenge Google Plus

Foursquare announced a new product that should help advertisers measure the effectiveness of their campaigns. With Attribution Powered by Foursquare, the company is making its data available to advertisers even if they don’t run campaigns in the Foursquare or Swarm apps. Naturally, that data is focused on location — that may be Foursquare’s big selling point compared to Facebook and Twitter, which have also been working to expand their ad capabilities beyond their own properties.

2014 - Google created unified marketing dashboard for small business - a new advantage over Foursquare

Google has unveiled a new marketing service for small business - Google My Business. It's a combination of former Google Local, Google Maps for business and social network Google+. In short, it's now a single place where you need to register your small business, so that it appeared everywhere - in Google's search, on Google Maps and in Google+ network. If your company had accounts / pages in these services, they are now automatically transferred to Google My Business. Of course, managing information in one place - is better than in three places. Besides, Google also created mobile (Android) that allows edit company info, view reviews and respond to them. However, the main problem with this service is that the social network Google+ is still not very popular place among your customers.