The proliferation of smart devices, such as smartphones/smartwatches, and tablets, is accompanied by an increased trust that users put on mobile applications for performing online transactions, social networking, storing credentials, and organizing photos and videos. As a matter of fact, any unauthorized access to such device, whether intentional or accidental, could lead to a loss of sensible data and a misuse of the user’s identity. Most popular user authentication schemes are based on “something user knows”, e.g., PIN/password, and “something user has”, e.g., physical characteristics, are no more considered secure enough to protect data. To this end, behavioral biometrics have attracted significant attention from academia and industry in recent years. This talk aims at explaining how these behaviors could be used to develop novel, user-friendly, and secure authentication mechanims.