A number of incentive schemes have been proposed to improve the performances of wireless networks. Wang et al.  propose a data-sharing scheme by exploiting local historical paths and users’ interest information. It can allow nodes to cooperatively deliver information of interest to one another via the chosen paths by utilizing few transmissions in delay tolerant networks. Chen et al.  propose a coalitional- gametheory-based incentive scheme to stimulate message forwarding in vehicular ad hoc networks. Wu et al.  use the gametheoretic approach to design a novel incentive scheme for stimulating selfish nodes in opportunistic networks, where the end-to-end paths are unstable. Wei et al.  introduce a usercentric reputation-based incentive protocol for delay-tolerant networks, where the game-theoretic framework is employed to design costs and the rewarding parameter in bundle forwarding. Mahmoud and Shen  propose an incentive system with a payment model in multihop wireless networks, by considering the difference between Web-based applications and cooperation simulation. Ning et al.  propose a credit-based incentive scheme to stimulate nodes, where the nodal communication is formulated as a two persons’ cooperative game by using the Nash theorem.
Gueguen et al.  present an incentive scheduling algorithm where the coverage extension is introduced to motivate and reward nodes’ cooperation. Im et al.  design an incentive protocol to support content sharing among users in the third- generation/wireless local area network dual-mode networks, which can also encourage the content provider to offer a discounted price for downloading high-quality content. Lee et al.  propose a secure incentive protocol to stimulate cooperative diffusion to advertise content over vehicular networks. Tseng et al.  design a reed-solomon-code-based incentive scheme to enhance security for vehicular content delivery.
Mobile social applications have attracted much attention. Liang et al.  propose a three-step data-forwarding scheme to enable efficient user cooperation and maintain privacy preservation in MSNs by introducing a new concept of social morality as a fundamental social feature of human society. Wang et al.  propose a cloud-based multicast scheme with a feedback mechanism in MSNs, which has two phases: precloud and inside-cloud. Niyato et al.  present a controlled coalitional game model for interaction between content providers and the network operator to distribute content. Bulut and Szymanski  present a friendship-based routing scheme for MSNs, which introduces a novel metric to accurately detect the quality of friendship and make the forwarding decisions. Wu and Wang  employ the internal social features of each node for routing, which has two unique processes, including social feature extraction and multipath routing.
Lee and Quek  propose a protocol for reliable device-to-device communications, where both the spatial user distribution and the communication distance distribution are considered. Zhang and Cao  introduce transient connected- componentaware data-forwarding strategies in MSNs to increase opportunistic contact to enhance the performance of data forwarding. Hu et al.  present a distributed multiage cooperative social protocol to disseminate content, where a content owner can multicast content to his social friends. Lin et al.  introduce a data-forwarding scheduling model and a back-induction algorithm for prompting nodes to forward messages to appropriate relay nodes.
Different from the aforementioned works, this chapter proposes a novel incentive- driven bundle delivery based on relay selection in MSNs. This work aims to stimulate selfish nodes to participate in data forwarding to improve system performance, including delivery ratio and delivery delay.