Launched last December, NameTag is a US-designed mobile app that uses facial recognition technology to help identify strangers. Simply take a photo of someone and the app will then search millions of photos online to match any profile associated with that person. You can also set up your own NameTag profile with links to your social media channels. Now available in beta version for Google Glass, users can scan directly from their live video feed. The service checks all social networks, dating sites and criminal databases. Now you can instantly see what substance is behind the pretty smile.