A new facial recognition app called Name Tag has been labelled a "serious threat" by privacy groups for its potential to divulge people's information against their will.

The US-based app is able to match photos taken of a subject to social media and dating profiles online, allowing users to find out information about strangers they see in person.

It will soon be available for Android, iOS and unofficially on Google Glass, with the creators claiming the app will make life easier for people looking for a date.

Despite claims that people will be able to opt-out of having their online information searched by the app, privacy advocates have criticised Name Tag for collecting and sharing information without consent.

"Companies like NameTag that want to aggregate all this information and combine it with deeply-invasive technology like facial recognition software without our permission completely expose all of us to any stranger on the street," Mike Rispoli, Communications Manager of Privacy International told news site PinkNews.

"They are kidding themselves that the primary user of such a system, if it was ever to work, would be some sweet person looking for a date. They seem to leave out all the other likely users: the police, private investigators, wanna-be stalkers, deranged people, or anyone seeking an unwanted romantic liaison."

Facial recognition technology incorporated into Google Glass was scrapped last year by the technology giant, citing similar privacy concerns with the software.

In a blogpost at the time, Google said: "We won't add facial recognition features to our products without having strong privacy protections in place. With that in mind, we won't be approving any facial recognition Glassware at this time."