Developing Cross-Display Applications Using the Really Easy Displays (RED) Framework. Roberto Calderon, Michael Blackstock, Rodger Lea, Sidney Fels Media And Graphics Interdisciplinary Centre The University of British Columbia roberto@alumni.ubc.ca, mblackst@magic.ubc.ca, rodgerl@ece.ubc.ca, ssfels@ece.ubc.ca Ricardo Almeida Departamento de Computação Universidade Federal de Sao Carlos ricardoalmeida@dc.ufscar.br ABSTRACT Public displays, mobile phones, and personal computers have become pervasive in public spaces. Yet, developing, de- ploying and maintaining applications that promote sponta- neous interaction between displays on these devices is often challenging. We present the Really Easy Displays (RED) Framework that provides easy development and deployment of multi-display applications. The Framework leverages the concept of an Internet of Things where physical (people, places, sensors and actuators) and digital entities (appli- cations, paragraphs, images, etc.) are able to interact with each other. This video outlines the motivation for our frame- work, talks through its usage and demonstrates the ease of developing and deploying a number of sample applications. Categories and Subject Descriptors H.4 [Information Systems Applications]: Miscellaneous 1. INTRODUCTION There has been significant research activity in the Ubiqui- tous Computing (Ubicomp) community in recent years to in- vestigate issues related to pervasive displays. These have in- cluded deployment considerations [2], technologies [6], their role in public places [1] and communities [5]. Although dis- plays are pervasive components of our world, developing and deploying applications that provide spontaneous interaction in multi-display scenarios is often challenging. In our own research over the last 6 years we have been exploring the use of pervasive displays in public settings, initially focussing on the necessary infrastructure for such displays [3], on engage- ment and casual use and more recently on understanding the core design issues when pairing personal displays with large screens [4]. During the course of this research, we have devel- oped and deployed a large number of infrastructure compo- nents and applications and have identified a number of key ‘practical’ issues associated with the development, deploy- ment and maintenance of multi-display applications. These include supporting and facilitating spontaneous interaction between devices (e.g. phones and situated screens) without the need for specialized software or hardware; simplifying application development, deployment, and maintenance to encourage the creation of a viable ecosystem for pervasive displays; and providing an easy-to-understand ontology of elements for multi-display interaction (e.g. gestural data, data streams, display content, context) that can be assem- bled together to create interactive applications. To meet these needs, we propose the Really Easy Displays (RED) Framework that leverages web technologies and an Internet of Things approach to allow the easy combination of physical objects (situated screens and mobile phones) and content often found associated with such objects (text, im- ages, or videos). In turn, these collections of physical and digital “things” can together form interactive applications that span multiple types of displays (mobile phones, tablets, large screens) and development platforms (Windows, Linux, Android, iOS). In this paper we discuss the motivation for our work, and how it has shaped the design of the RED Framework for cross-display interactive applications. We provide an overview of the framework’s architecture and illustrate its ease of use. We discuss the lessons learned from initial usage of the Framework, and outline future work needed to improve the proposed technology. 2. MOTIVATION The proliferation of public displays and personal devices such as cell phones or tablets offers a unique and growing environment for multi-screen interaction.To support these and similar requirements we designed a set of abstractions and developed a core publish/subscribe platform providing RESTful web services to allow for the easy development of interactive multi-display applications. Once built, we have used this platform to develop and deploy several applica- tions that explored use of personal mobile devices and large public screens. According to our previous findings, mobile phones play a significant role when more interaction accu- racy or privacy is required. These personal displays promote a stronger feeling of possession, reducing the embarrassment of utilizing public screens. Large displays, by contrast, allow for an increased sense of social engagement and accessibility of content to a broader audience.