The growth of cities causes some difficulties. Living in metropolises gets easier by smart city concepts. However, only Internet of Things is being used nowadays for smart cities by Long Range Wi-Fi. These projects are expensive and hard to set up in big cities scale. Our aim was to find new solutions for the listed problems by using an existing technology. RDS Technology fits our purposes. It does not need so many transmitters as Long Range Wi-Fi needs, its price is as half of Internet of Things’ and it has been already used over 1 billion devices such as modern cars’ radios or smart phones. But we are using this technology to inform public in emergency situations, reduce energy and water consumption, give way to priority vehicles, manage barriers to prevent criminals from escaping etc.