Opportunistic scheduling was initially proposed to exploit user channel diversity for network capacity enhancement. However, the achievable gain of opportunistic schedulers is generally restrained due to fairness considerations which impose a tradeoff between fairness and throughput. In this dissertation, we show via analysis and simulation that opportunistic scheduling not only increases network throughput dramatically, but also can be fair to the users when they cooperate, in particular by forming clusters. We propose to leverage smartphone’s dual-radio interface capabilities to form clusters among mobile users, and we design simple and scalable cluster-based opportunistic scheduling strategies which would incentivize mobile users to form clusters. We use a coalitional game theory approach to analyze the cluster formation mechanism, and show that proportional fair-based intra-cluster payoff distribution would bring significant incentive to all mobile users regardless of their channel quality.