They have become extremely popular recently and are potentially important sources of sensor data. They are typically
equipped with various sensing faculties and wireless capabilities that allow them to produce data and upload the data to the Internet. As an example, a sample list of mobile devices and their corresponding sensing capabilities are provided
in Table 1. Future sensing capabilities on smartphones include ECG (for medical purposes, e.g., ithlete, H’andy Sana), poisonous chemical detection (e.g., cell-all), and air quality sensors (e.g.,Intel’s EPIC, Fig. 1).