Arif Akhmedzade- TRANZZO LTD.
Nice app from facebook, uses also geolocation and has all necessary information.Can Comertoglu- Product @OneDrive (prev: Vimeo, Amzn)
Pretty much the simplest - create an event, and you can manage everything you asked for (send invites, collect RSVPs, location, time) and allows for a simple way for folks to send photos/videos they take to the group page so everyone has access!