Embodiments of the invention are directed to systems, devices, and methods for using mobile devices to detect a simulated source, and games and training exercises using these systems, devices, and methods. In some embodiments, the source may be a simulated hazardous material that emits energy, particles, or vapors that can also be simulated by the mobile devices. In such embodiments, the systems, devices, and methods can be used to simulate an incident involving the release of hazardous materials such as, for example, a chemical or radioactive material spill or attack by chemical, biological, nuclear, or radioactive (dirty bomb) weapons. In other embodiments, the system can be used to simulate an object used in a game such as a ball, puck, or goal and monitor movement of the object and players using a mobile device.