Sonar, a new iPhone app, which launched at the TechCrunch Disrupt conference in New York this week, is one of the six finalists in the Disrupt Battlefield competition for new start-ups.

The app uses the Foursquare API to allow users to check in at a given location. It tells the user who else is there, and how they might be connected through comparing publicly-available data from social networks like Facebook and Twitter.

On checking in at the Technology Voice HQ, I discovered that one user was next door. He followed several of my followers and people I followed on Twitter. We had no mutual friends on Facebook, nor did he ‘like’ any of the bands that I like, but if he was a massive Smashing Pumpkins fan like me, Sonar would have told me that too.

During their launch, founder Brett Martin evoked the memory familiar to many of us, of being at a party or conference, and lingering by the bar texting or tweeting to friends miles away. The idea behind Sonar is that it will utilise social media to help forge real-life connections.

Sonar offers the facility of sending connected people a personalised tweet, saying, for example that you both have a mutual friend or interest, and offering to arrange to meet. This function could prove attractive to those who find introductions difficult, or in the case of a large business conference, make locating potential acquaintances easier.

For all the buzz being generated by Sonar though, it seems more likely that its business networking potential will be where it enjoys success rather than in the social sphere. After all, even if the guy next door does listen to the same music, this does not mean that I or anybody else wants to be approached to talk about it. Real social relationships are more complicated than a choice between “like” or “ignore”, and that algorithm has yet to be written down.

However, in the business networking space, Sonar could make a big impression. Should it, as promised, incorporate Linkedin data, conferences and business events could become a lot more streamlined, as conference-goers benefit from being able to see who has worked in what sphere and focus their networking accordingly.

Sonar is currently free to use but during their Battlefield pitch Brett Martin hinted that the company might adopt a freemium model. For a fee users will be able to promote their profile so that in crowded areas their profiles are found first. The large amount of data that they will access will also likely be used to generate revenue.

For now, all it is generating is hype, but if Sonar manages get over the initial hurdle of attracting enough initial users that it becomes useful, then there is a very real possibility that it can live up to the hype, and follow whatever trajectory along which its users lead it.