Use FaceLock to protect your apps with your face! Your face is the key to unlock them. You can use FaceLock to protect your mobile phone against theft, by locking apps (applock), as a gallery lock or to lock whatsapp and facebook so nobody can spy on you.
This free version will lock the protected apps: market, task manager, settings and one app of your choice. *PLEASE* DON'T RATE THE APP BEFORE READING WHAT THE APP IS SUPPOSED TO DO. Now PIN access is also available in this FREE version! Some tips on how to do the training properly: http://www.facelock.mobi/tips-and-faq
About security: task manager, settings and market are protected so no one can kill or uninstall FaceLock out of the box. Face recognition is reliable and safe with the default settings. For recognition in difficult lighting you can train more images whenever you are not recognized. For increased security you can raise the security level.
By downloading this software you agree to the terms of the end-user license agreement: http://www.facelock.mobi/facelock-for-apps/eula