We are facilitating software development for mobile social robots that operate `in the wild': that is, in real daily environments such as shopping malls. One fundamental difficulty in development is testing unfinished programs on a real robot and in the presence of people, because this process can take a significantly time-consuming. To ease the software development, we developed a simulator that allows the simulation of interactions among people, and interactions between people and the robot. With a user study, we analyzed how people's working process changed and evaluated the amount of time they saved in software development with the simulator.