An embodiment of the invention provides an operation method for a portable device. The method comprises steps of mounting a first partition of a flash memory to an application processor, wherein a calibration data is stored in the first partition and the first partition is read only by the application processor; mounting a second partition of the flash memory to the application processor, wherein a radio data is stored in the second partition and the second partition can be read or written by the application processor; transmitting the calibration data and the radio data to a communication processor by the application processor; the communication processor operating according to the calibration data and the radio data.