Since both people and goods move in the urban environment, an efficient and effective transport network that ensures a smooth sharing of passengers and freight is an essential element in cities life and development. For this purpose, people and goods transportation streams need to be synchronized so that a better use of available transportation resources is desired and a higher quality of service is guaranteed. First, we give an overview of the latest innovations for shared mobility systems, including those combining people and freight transportation. Then, we present a model that integrates freight deliveries to a scheduled line for people transportation where the aim is to use the underused capacity to transport freight simultaneously with passengers. We assume passenger demand, and thus the number of available places for transporting freight, to be stochastic. As such, we model this problem as a two-stage stochastic problem and we provide a MIP formulation and sample average approximation (SAA) method along with an Adaptive Large Neighborhood Search (ALNS) algorithm to solve the stochastic optimization problem. Finally, we give some insights and promising directions for future research.