The advances in the areas of microelectronics and telecommunications are helping to materialize the vision of a pervasive computing model through the incorporation of sensors and communication interfaces into objects of everyday life. In recent years, there has been a growing interest in crowd assisted sensing applications, in which people serve as the building block that can be exploited to offer pervasive opportunistic sensing at scale. This paper describes a new crowd assisted pervasive opportunistic sensing framework able of exploiting people's mobility to overcome the coverage limitation of sensors and the diversity of devices, expanding the scale of sensing applications.