The number and capabilities of IoT devices will exponentially grow over the next years. Together with the pervasive diffusion of smart personal mobile devices this opens up unprecedented opportunities for contextualised services provided to mobile users, based on their current interests and behaviours. In addition, most of these services will be content-centric rather than host-centric. Cloud computing and Information-Centric Networking (ICN) are therefore two key technologies in this perspective. In both cases, solutions are typically designed for global Internet platforms, while mobile nodes are seen as edge devices from which data are fetched and sent back through pervasive wireless networks (typically, LTE). However, it is questionable whether such an approach will work as expected, e.g., due to data privacy concerns and expected bandwidth shortage of even last-generation cellular networks. In this paper we present a general framework where global cloud and ICN platforms are complemented in a totally synergic way by local clouds formed at the edge of the network by mobile devices, where service provisioning and data management functionalities are offloaded whenever possible (and appropriate). This results in a multi-layer, content- and service-centric approach to IoT data management and service provisioning. We then present performance evaluation results from applying this framework to a specific case where data-centric services are jointly provided by edge devices and by a global cloud platform. Results show that this approach is very promising, as it is able to drastically cut the related cellular-network traffic, and, at the same time, improve the effectiveness of service provisioning to users.