A location-dependent security method and system for a portable electronic device is disclosed. Without requiring that the user enter any location information, the system determines one or more familiar areas for the device based on locations where the device has received at least a threshold amount of successful user authentication entries. Thereafter, when a user attempts to access the device or an application of the device, the device will implement a first authentication process if the device is in one of the familiar areas, or a different authentication process if the device is not in one of the familiar areas.