A mobile electronic device and method are presented. An input operation by a user is received, functions are stored, a remaining battery capacity is measured, and a first image is displayed indicating the remaining battery capacity and full capacity. Battery blocks are set by dividing the full capacity, if an input is entered when the first image is displayed to provide a battery blocks set up. A capacity ratio is calculated based on capacity of each of the battery blocks and the full capacity, and a remaining battery block capacity of the battery blocks is calculated based on the capacity ratio. A function is allocated to the battery blocks, and second images are displayed indicating the capacity ratio and the remaining battery block capacity. The function allocated to the battery blocks for the battery block images is displayed, when the battery blocks are set.