A mobile device is provided. The mobile device includes multiple cameras and a processor configured to perform image processing on image data output from the cameras. The mobile device supports, as a standby mode for one or more standby cameras from which an image is not provided among the multiple cameras, a sensor standby mode in which the one or more standby cameras does not perform an image sensing operation that generates the image data, a low frames per second (FPS) post standby mode in which the one or more standby cameras performs the image sensing operation that generates the image data with a low frame rate lower than a normal frame rate and the processor does not perform the image processing on the image data output from the one or more standby cameras, and a normal FPS post standby mode in which the one or more standby cameras performs the image sensing operation that generates the image data with the normal frame rate and the processor does not perform the image processing on the image data output from the one or more standby cameras.