One aspect of the invention is a method for identifying at least one property of data. The position specifying unit specifies a position of a second apparatus on a display screen of a first apparatus. A difference calculation device calculates a difference of the detected phase shift over time, and a positioning device determines a target position where the difference is produced. When an operator places the guiding magnet in a vicinity of the chip, the guiding magnet produces a proximal magnetic field gradient at a location of each of the plurality of magnetic valves.