Making web applications run in a decentralized though collaborative way, with connectivity disruptions, is a challenging task. Opportunistic networking offers a way to be independent from a fixed infrastructure and cope with intermittent connectivity by leveraging both the mobility of nodes and their transient radio contacts. This paper presents an environment that facilitates the development of web applications deployed in opportunistic networks built out of smartphones. In order to overcome the technology hindrance regarding smartphones’ ad hoc communication capabilities, our contribution externalizes opportunistic networking to a dedicated device. On top of this support for smartphones, we propose an implementation of a programming model called foglet that allows web browsers to share consistent data structures. This implementation helps achieving decentralized applications distributed across mobile web browsers without relying on any network infrastructure.