An electronic device that includes a processor, an output device connected to the processor for issuing a stimulus to a user of the device, at least one input device connected to the processor and responsive to user input activity, and a device lock module associated with the processor for (i) implementing restrictions on user access to the device if user input activity falls below a threshold; and (ii) redetermining the threshold if a stimulus is issued by the output device. Also, a mobile device that includes a processor, at least a first input device connected to the processor for providing input signals thereto, an output device connected to the processor for providing output to a user of the mobile device, the processor being configured for determining location information for the mobile device based on input signals received from the first input device and adjusting an operating characteristic of the electronic device based on the determined location information.