There has been widespread recognition of the existence of a gap between electronic data and paper data. Past techniques to solve this problem have met with little success, and have been largely focused around the desktop environment. In this paper we present PocketPad, a mobile application framework that supports the retrieval, and interaction with content in the digital world through Anoto-based pen and paper. The specific advantage provided by PocketPad is the repurposing of digital content through a human-in-the-loop port of electronic information stored in the repository onto a digital canvas. This electronic content is combined with strokes rendered on pen and paper, bringing the advantages of pen and paper and the flexibility of electronic content together in a mobile framework. We describe each application component, and their role in supporting mobile paper-based interaction. We also describe testing that studies the ability of subjects to perform visual spatial registration of Pocket PC-based content with pen and paper based content to validate the interaction supported by the PocketPad system.
