Abstract: Methods and apparatus for controlling the execution of individual functions performed by a multi-function battery-powered electronic device, such a cellular telephone. The device user assigns priority values to each function. When the execution of a function is requested, the system determines whether or not the current battery charge level is greater than a threshold level determined by the requested function's assigned priority. If the battery level is too low, the user is alerted with an ignorable warning. Priority levels can be assigned to individual entries in a “phone book” to discourage conversations with low priority parties in order to conserve the battery to permit later calls to or from high priority numbers.