Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Nightly - One part dating, one part social, one part nightlife
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
FairTrip - The sustainable travel app
Bylde - Bylde is a SaaS platform you can use to Start, Manage and Grow your groups and communities.
Askfortask - On-demand App for pick up , cleaning, plumbing, handyman, moving and other tasks in your area