Alkarta - Find happenings in your city.
Attendize Event Ticketing - Attendize is a free & open-source ticket selling and event management platform
Party with a Local - Party with a Local is a free app that connects travelers with locals that want to party.
Mutronome for iOS - Practice drums with Apple Music
Rally by Eventbrite - Find the best local events and rally your friends to join
Eventible - Event reviews from real attendees