An RFID tag is used to determine the presence or absence of a user. Rules or instructions responsive to this presence or absence are implemented to control a device or multiple devices accordingly. In this manner, a device can be maintained in a normal operating mode if a user is present, even though a user is not actively interacting with the device. Moreover, the device can be shut down or locked or be on restricted access if an authorized user is no longer in the presence of the device.