Nowadays, the idea of tracking and counting people at specific places has been subject of many studies. The main objective is to consider and transform people into active actors of future Smart Cities. The context of this thesis is the research and exploration of Automated Passenger Counting (APC) systems applied to public transport. The objective is to present a clear picture of the opportunities and challenges of APC systems derived from the study and benchmarking of different solutions present on the market. The benchmarking is based on a multicriteria analysis considering devices' characteristics and business strategies of the selling companies. The idea is to offer an explicit definition of the main characteristics of the system’s components, to allow a more informed and conscious allocation of resources and smarter decision processes, for both clients and sellers.