From the website:

Whether you are interested in meeting locals or fellow travelers during a trip or finding a "trip buddy" so you don't have to travel alone, TripUp gets you connected before you depart. Plus, as a TripUp member you can share your travel videos, journals and photos, find current and candid information about your destination from our member-created travel reviews and Trip Forum, ask a "trip guru" for insider advice about your destination, organize group trips with Tripvite, and explore all of the fun places your tripmates have discovered.