In recent years, mobile phones have become widely used in many countries. However, these phones clearly are not just used for conversations, but also as information terminals for e-mail, Web searches, and a variety of Internet services. They also meet consumers’ entertainment needs for playing games, viewing movies, watching digital TV, and a host of other functions. Currently, mobile handsets are equipped with the same functionality as credit cards and railway commuter passes. On the whole, the importance of mobile phones in daily life has been rapidly increasing.

On the other hand, the illegal use of mobile phones has also risen, and there is a growing risk that e-mail addresses and other personal information can fall into the wrong hands when handsets are lost or stolen. Mobile phones need a reliable and easy-to-use security system to be accepted by users. An identification system based on facial recognition succeeds in protecting personal information and preventing its improper use when a mobile handset is lost or stolen.