The work in this paper is a systematic research and engineering effort in exploring the design space of multi-interface wireless repeater systems. We present the design, implementation and evaluation of a wireless repeater system, Multifacet, which opportunistically utilizes multiple interfaces to enhance capacity. The system is designed to be transparent to application endpoints and does not need any end application modifications for adoption. Multifacet incorporates several techniques to achieve efficient bandwidth utilization across multiple interfaces -- (a) coordinated channel sharing, (b) a simplified backpressure based striping technique, (c) a single link abstraction, and (d) the ability to seamlessly migrate a client to the optimal channel. Multifacet is implemented on off-the-shelf dual band wireless repeater and demonstrates high speeds (337 Mbps) operation. On average, Multifacet performs 50% better than traditional AP/repeater setups, and in the best case, more than 2x better.

We present a long term and large scale study of the experience of mobile users through two popular but contrasting applications in the wild. To conduct this study, we implemented a measurement framework and library, called Insight, which has been deployed on these two applications that are available through Apple's App Store and Google's Android Market. One of them, Parallel Kingdom (PK), is a popular massively multiplayer online role-playing game (MMORPG) which has over a million unique users distributed more than 120 countries. The other application, StudyBlue (SB), is an educational application with over 160,000 unique users. Our study spans most of the life of the PK game (more than 3 years) while our deployment with SB has been running for over a year now. We use Insight to collect diverse information about network behavior, application usage and footprints, platform statistics, user actions, and various factors affecting application revenues.