Mobile devices provide security based on geographic location. With such a technique, a mobile device may automatically check its current location against geographic information as to the location(s) in which it is permitted to operate. When the user attempts access to the device, the mobile device will prompt the user for his/her credential only if the geographic location matches an allowed location. The user gains access then by inputting information corresponding to the credential, e.g. username and password, of a valid user. In the examples, if the geographic location does not match an allowed location, the mobile device provides a warning to the user, and the user is not allowed to enter any credential information. Optionally, the mobile device may send an alert message about the device being taken outside a specified boundary, e.g. to report the situation to other personnel.