Abstract : In this paper, we present a middleware architecture for dependable mobile systems and an experimentation platform for its evaluation. The proposed architecture includes three building blocks tailored for mobile cooperative applications: a Proximity Map, a Trust and Cooperation Oracle, and a Cooperative Data Backup service. To illustrate our platform, we developed a Distributed Black-box application, whose aim is to record critical data while tolerating the failure of a node, and implemented a hardware evaluation platform of mobile systems for experimenting with the application. We provide here some insights on the development of the platform, focusing on wireless communication emulation via signal attenuation.