Architecture that enables users to define user interests, and when two or more people with matching interests (mutual) are identified in the same geographical area, the architecture actively notifies either one or both of the users (e.g., based on a given scenario). After being notified, either or both users can decide how to act (e.g., the user that wants to buy the car can call the user that wants to sell the car and then set a meeting at a suitable time). The architecture automatically creates dynamic geo-fences in association with users to perform different location-based matching scenarios. The locations of the users are continuously identified as the users move in a geographical area. When a matching interest is identified, the architecture actively notifies the users of items that might be of interest and which are currently occurring in the user vicinity.