1. An apparatus comprising: a storing unit configured to store a three-dimensional model; an obtaining unit configured to measure position data of a predetermined part of a user; a determination unit configured to determine timing of executing a movement simulation of the three-dimensional model based on the position of the predetermined part of the user; an executing unit configured to execute the movement simulation of the three-dimensional model; and a synthesizing unit configured to synthesize an image which represents a result of the movement simulation with a real space image.