05/22/2012 12:54 pm ET Updated Jul 22, 2012

Buon Compleanno, Sonar!

New York has a track record in networking tech. It's 1956, and Brooklynite Alfred Neustadter hacks together a device that keeps all your business contacts on a single rotating spindle file; the Rolodex goes on to become a hallmark of meeting people for the rest of the century.

Five and a half decades later, it's a different world -- one that sees, say, a couple billion mobile app downloads per month, and NYC-based Sonar is looking to make its own mark on how people link up. The mobile app, which launched a year ago today, serves up small world moments by letting you see who's around you and how you're connected to them. Originally based on Foursquare data, the app now ropes in Twitter, Facebook, and LinkedIn activity, not just check-ins.

The founder, Brett Martin, personifies the app itself. He grew up in the one and only single family home on the Ocean City (Maryland, not New Jersey) boardwalk, a place that's empty (even closed up) for most of the year. But come summer, it's a visitor firehose. Brett loved this and recognized the need for virtual "icebreakers" to facilitate meeting as many folks as possible -- a meetup mentality led to the creation of Sonar.

In line with its anniversary, Sonar's releasing an update on Wednesday at 2:30 p.m. that has Wakefield intrigued (we're sworn to secrecy -- you'll have to tune in here to watch it).

Now go forth (and explore this great wide small world).