Apparatus with printing unit

A stable condition for a printing operation in an apparatus (1) having a printer unit (4) and a battery unit (7), eliminating problems arising from lack of battery power during the printing operation performed by the battery, specifically for a portable apparatus using the battery, is obtained by an apparatus (1) having the printer unit (4) in which the printing operation is performed by processing data inputted from outside and/or data stored therein. The apparatus (1) having the printer unit (4) can be activated by the battery and perform communication with the battery so that, based on received information related to the remaining power of the battery as well as calculating the printing enabling power based on, for example, temperatures outside and/or inside the apparatus and the amount of data to be printed out, the remaining power of the battery is compared with the printing enabling power. If the remaining power of the battery is lower than the printing enabling power, then a condition of inability of execution of printing operation is established and informed to a user in order to restrain printing action.