Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.

PartyUP - See videos from the best nightlife venues in your city.

Google Groups - Google Groups allows you to create and participate in online forums and email-based groups with a rich experience for community conversations.

WOOdate - Find, customize, and plan your entire date in one place.

Eventbrite - Discover Great Events or Create Your Own & Sell Tickets

Tack App - Interact with your local community