The technology disclosed relates to identifying and notifying a user of nearby attendees at a mega attendance event who are in user's social graph by comparing the user's social graph to a list of event attendees. The identified attendees can be stratified into social graph tags that annotate, categorize and prioritize other users in the user's social graph. The technology disclosed also relates to identifying and notifying the user of nearby attendees of sessions at the event who meet introduction preferences of the user by finding matches between introduction preference attributes specified by the user and attributes of the attendees provided by the list of event attendees.