Add a face recognition login feature to your iOS app and let your users authenticate without typing passwords or connecting to social networks.
Follow the instructions on sdk_exampleViewController.mm
Basically you'll have to store the current user login information in a special key on a NSUserDefaults entry after the first time the user logs in. When the user signs out, the app moves this data safely inside the app from this current key to a secret one. Now, when the user tries to login using his face, the app will validate his session and move the login data back to the default key in the app, dimissing the login view.
Download the GeoPapyrus app to see it in action https://itunes.apple.com/us/app/geopapyrus/id603735261?mt=8
Drop us a line at support@geopapyrus.com