An image processing apparatus capable of facilitating synchronization of a maintenance moving image between an image processing apparatus and a mobile information terminal, thereby making it possible to more efficiently show the moving image to a user who performs a maintenance operation. The mobile information terminal is registered as a distribution destination of the moving image. The moving image for current reproduction and display on the apparatus and information of the reproduction position of the moving image are distributed to the terminal to thereby cause the terminal to reproduce and display the moving image from the position. The position is changed based on information of a change in the reproduction position received from the terminal. When the position is changed on the image apparatus, information of a change in the position is transmitted to the terminal, to thereby cause the terminal to change the position.