A technique is disclosed that changes one or more properties of a user interface at a telecommunications terminal based on an incoming call. When a first caller calls the telephone number of the terminal directly and the terminal answers the call, the terminal presents the direct call to the user through a first user interface. When a second caller calls a telephone number that is associated with a data-processing system and the call is then redirected to the terminal, the terminal presents the redirected call to the user through a second user interface. The telecommunications terminal can be a cell phone that belongs to a user, and the data-processing system can be a private branch exchange that serves an office enterprise network that the user belongs to, wherein the private branch exchange extends the call to the user's cell phone when the user is out of the office.