1. A method for saving power in a mobile terminal, comprising: detecting occurrence of an activation condition, the activation condition corresponding to at least one non-essential telephone function; measuring a remaining power capacity of a battery in response to detection of the activation condition; determining whether the remaining power capacity of the battery is smaller than a prescribed reference value; and automatically de-activating the at least one non-essential telephone function when the remaining power capacity is smaller than the prescribed reference value, wherein deactivation of the at least one non-essential telephone function is not determined by a user and wherein when a power capacity of the battery is determined to be larger than the prescribed reference value, the mobile terminal is automatically configured to allow operation of the at least one non-essential telephone function.