Opportunistic networks are usually formed spontaneously by mobile devices equipped with short range wireless communication interfaces. Designing and implementing a routing protocol to support both service discovery and delivery in such kinds of networks is a challenging problem on account of frequent disconnections and topology changes. In these networks one of the most important issues relies on the selection of the best intermediate node(s) to forward the messages towards their destination(s). In this paper, we propose a new location-based opportunistic routing protocol enabling a bandwidth-efficient service discovery and delivery in a wide area network composed of numerous mobile devices. This protocol implements self-pruning heuristics allowing mobile devices to decide whether they efficiently contribute in the delivery of the messages they receive from their neighbors. This protocol was validated through simulations, which proved its efficiency and cost-effectiveness.