L. Cowan, N. Weibel, W. Griswold, L. Pina, and J. Hollan. Projector Phone Use: Practices and Social Implications, Personal and Ubiquitous Computing (PUC), February 2011. 
Abstract
Phones with integrated pico projectors are starting to be marketed as devices for business presentations and media viewing, and researchers are beginning to design projection-specific applications and interaction techniques to explore a broader array of possible uses. To begin to document how people use projector phones outside the laboratory, we present the results of a 4-week exploratory field study of naturalistic use of commodity projector phones. In our analysis, we consider how context, such as group size, relationships, and locale, influences projector phone use. A key observation is that users can readily exploit the new facilities of these devices to author interesting effects by employing representational techniques such as superimposition, scaling, translation, and motion. Thus, even the “basic” projector phone platform affords novel interaction modalities. Finally, we discuss the social implications of projector phone use for privacy and control, extrapolating from our observations to envision a future in which these devices are ubiquitous. With ubiquity, projector phone use may become problematic in public settings, motivating new rules of etiquette and perhaps laws, yet it may also engender new forms of creative expression.