Geosocial networking allows users to interact relative to their current locations. Web mapping services with geocoding data for places (streets, buildings, and parks) can be used with geotagged information (meetups, concert events, nightclubs or restaurant reviews) to match users with a place, event or local group to socialize in or enable a group of users to decide on a meeting activity. Popular geosocial applications like Yelp, Gowalla, Facebook Places and Foursquare allow users to share their locations as well as recommendations for locations or 'venues'. New applications follow other approaches and do not focus on places. Instead, they allow users to enrich maps with their own points of interest and build kind of travel books for themselves. At the same time users can explore overlays of other users as collaborative extension.