Two applications of the smartphone in college physics experiment，i． e．，demonstrating beat phenomena and demonstrating three-dimensional vision of human eye，were explored．The frequency generator app was installed on a smart phone to make the phone output two simple harmonic sound waves with close frequency at the same time，and the beat phenomenon in sound could be heard． The beat frequency was measured and it was confirmed that the beat frequency is equal to the difference between the frequencies of two simple harmonic vibrations．A picture was taken using a smartphone．Another picture was taken after moving the smartphone 6．0 cm，i．e．，about the distance of two pupils of human eyes．These two pictures were shown on the smartphone at the same time．Then the smartphone was put in a VＲ glasses，and three-dimensional image was observed by the VＲ glasses．Three-dimensional vision of human eye was demonstrated by this means．