Abstract: The invention relates to a device for automatically opening or closing a window or a door and system and method for controlling and managing indoor air quality via the Internet. The system monitors indoor air parameters through sensors, and when these parameters reach predefined user thresholds, provides room ventilation through natural air convection by automated opening/closing of doors and/or windows. The automatic opening/closing device (26) consists of a housing with means for fixed attachment to a window or a door. The housing hosts: a stepper motor (16) and a means for transforming the rotary motion into a linear motion (9, 13) which drives an extended flexible connection (10, 11). The flexible connection (10, 11) pushes or pulls a support element (1) which is mounted on a window/door, thereby opening the window or door.