A system and method employing geo-tagging and/or biometric identification is employed for registration and management of a mass gathering event. Electronic devices are configured for capturing data and geo-tagging the captured data using the geographic position of the electronic device. Data relating thereto and related data concerning persons and/or locations and/or other things are associated with a unique identifier and are stored in a relational database from when they may be retrieved and processed for generating a response or other follow up which can be communicated to an electronic device. Responses are communicated to the electronic device that captured the data relating to the particular group of registrants or to an electronic device using its geographic location.