Wikipedia
Face.com was a Tel Aviv-based technology company that developed a platform for efficient and accurate facial recognition in photos uploaded via web and mobile applications. Face.com apps and API services scan billions of photos monthly and tag faces in those photos, tying them directly to available social networking information. As of February, 2011, the company had “discovered” 18 billion faces across its API and Facebook applications.
The company was established in 2009, and maintains an office in Tel Aviv, Israel with 10 full-time employees. Face.com has developed and released two Facebook applications: Photo Finder and Photo Tagger. Photo Finder allows users to find untagged pictures of themselves as well as friends on Facebook and then tag those photos. Photo Tagger enables bulk-tagging of faces that appear in multiple photos uploaded to the Facebook website. On June 18, 2012, the company announced that it has been acquired by Facebook. With this announcement they also announced that they are winding up their api's to 'focus on new products at Facebook'