It is often said that the introduction of a new service based on a new technology is important to activate the market and to obtain larger share in the market of mobile phone. At the same time, however, it is also said that there is an effect of network externality in the mobile phone market that tends to fix the share in the market and that it is difficult to change the share once the market reaches saturation. In this paper, we study the case of camera implemented cellular feature phone that was first introduced by a Japanese cellular phone service firm under the circumstance that the market is almost saturated. We analyze the market based on an agent model simulation. One can see that there is some amount of market share changes due to the introduction of the new technology even if the market is almost saturated.