Automatically changing device property values for a secondary user of a device

A device property control system determines whether a current user of a device is an owner of the device, a trusted secondary user of the device, or an untrusted secondary user of the device. The system maintains device property values for the owner as well as each trusted secondary user of the device. When the current user of the device changes, the system determines whether the current user is the owner or a trusted secondary user and if so changes the device property values to those previously used by the owner or one of the trusted secondary users (whichever is the current user of the device). However, if the current user is an untrusted secondary user, the device property control system changes the device property values to demonstration mode device property values that are expected to best demonstrate the capabilities of the device.