During a telephone call between a telephone user and an interactive response system, the user is enabled to use only his voice and key presses on a numeric keypad of his telephone to interactively specify information that can be used to control delivery of content to a visual display of, or a storage medium accessible by, a target telephone which may be a land-line phone, a mobile phone, or some other device acting as a telecommunications device. The target telephone has a visual display or a memory to display or store the delivered content, which may include ringtones, text messages, games, wallpapers, ring-back tones, video clips, web pages, applications, or links to information. The user is enabled to engage in an interaction with the response system that is representative of an interaction between the user and a server connected to the Internet. On behalf of the user, a separate interaction is conducted with the server through the Internet based on the representative interaction. Information is received that can be used to identify the user and the target device. Based on the received information, user authentication information is transmitted to the user, the authentication information is received from the user, and the user is allowed to access a service.