The approach described here attempts to overcome foot-mounted limitations, contrary to a majority of current implementations of inertial navigation systems (INS). The aim of our development is to maintain repeatable performance, especially without step counting, while carefully dealing with the mobility requirements and the computation cost. The inertial measurement unit (IMU) is belt mounted to facilitate the equipment of the user. The pedestrian trajectory is computed in real time. The resulting position is transmitted and displayed to the user on a smartphone where no specific application is installed. The description of our indoor experiments reveals the potential of this approach, in terms of positioning performance, with more than 75% of our experiments when the relative start-end error remains below 5% of the total traveled distance.