The idea also has found unique traction in the gay community.
A male-only app called Grindr says it has more than 900,000 users in 162 countries.
Grindr has made meeting people faster and easier, he said. There's no need to have e-mails back and forth, SMS's back and forth," he said.
"The incentive is just to go meet." In effect, Grindr also works as a kind of digital "gaydar," allowing people who are interested in same-sex relationships to identify each other without the awkwardness of having to ask someone if they're gay or not.
A grid of photos showed women who, at that very moment, were within a certain radius of Scott and his GPS-enabled phone.
Joel Simkhai, the 33-year-old CEO and founder of that app, said Grindr users typically range from about 20 to 30.
Simkhai said he created the app partly because he was having trouble finding men to hook up with and date. If somebody's 200 feet away from you, then go meet them, go say hi for five minutes.
The apps tend not to say exactly where a person is located, and, on Skout and Grindr, you can turn off the location-aware feature if you choose.
Most of the apps rely on instant messaging as a way to break the ice before a real-world conversation takes place.