An improvement of pedestrian infrastructure, as well as a higher amount of people walking in inner city areas are desirable. Pedestrian volumes can encourage urban planners and policymakers to argue for an enhancement of walkability. The growing number of mobile devices, equipped with Bluetooth and Wi-Fi interfaces, creates new possibilities in pedestrian data collection in indoor and outdoor situations. An automatic, cost effective pedestrian counting device, operating with Wi-Fi and Bluetooth data to acquire pedestrian information, is highly welcomed. Preliminary tests indicated that Bluetooth and Wi-Fi signals could indeed be utilized for the detection of pedestrians in urban areas. This paper describes the development and testing of a sensor, used for detecting pedestrians via Bluetooth and Wi-Fi signals in urban areas. Implemented controlled and open field tests indicated the practical usability of such a device for the collection of pedestrian data.