Various mobile communication terminals, their operational sequences, and related methods of using such terminals for providing a user with seamless operations in environments with an enhanced security. More particularly, such terminals, sequences, and methods authenticate a user as well as display at least one advertisement screen or content screen on display units, all in response to a single authentication (user) sub-input. Further mobile communication terminals, their operational sequences, and related methods are disclosed where such terminals employ multiple authentication operations but authenticate a user while displaying such screens, all in response to the same number of authentication (user) sub-inputs, thereby ensuring both seamless and secure operations for the user.