Although network connectivity is becoming ubiquitous thanks to global cellular networks, accessing multimedia resources is still expensive, and concurrent access to the same resources in dense urban areas can raise scalability issues. This would be typically the case for context-related resources, such as trailers in a movie theater. In this paper, we introduce a peer to peer protocol enabling cooperative download using Bluetooth. The idea is to balance over a set of users the download of common resources, in order to reduce the network load and cost. The protocol can also be used for locally sharing resources between the units.