CAOS aims to provide a reference forum targeted not only to the community of researcher working on networking technologies for OSN, but it aims at engaging a multidisciplinary community of researchers working at the intersection between computer networking, complex networks, Big Data analytics, focusing on network technologies and abstractions for OSN. Therefore, the workshop also welcomes submissions applying a wide range of (computer- and network-science) techniques and tools to OSN for investigating the properties and roles of the network of (online) social relationships in the various sectors of the society (e.g., politics, economics, finance, health, entertainment).