The location-based social network Loopt, just announced and demoed its native iPhone application onstage at WWDC. The application, which will be free at launch, helps you connect with and find friends around you. Using the location technology built in to the iPhone, Loopt will drop pins onto a map, showing where your friends are.
Loopt also contains other social-networking features, such as calling, texting, and sending invitations to meet up. The example used was seeing if any friends are in your area for lunch. Once you have located friends, you can send them an invitation for lunch, and if they agree, you will be one touch away from directions to their location. As Sam Altman from Loopt put it, "You will never have to eat alone, or at a bad restaurant again."
This is an exciting step in bringing location-based networking into the mainstream. With native third-party applications for the iPhone and the rumored GPS feature, expect to see many applications leveraging these same sorts of capabilities in the future.