This book is the result of an international program of conferences and round tables in Paris 1 Sorbonne with participants from Japan, Canada, England, Switzerland, Malta, and France. The participants consider the growing number of artistic, digital, fictional, and game devices that are based on user mobility and interaction through digital interfaces. Through exploration, experimentation, and the creation of alternate reality art devices, questions about the limits between real, virtual, and fictional worlds are discussed. The characteristics of these three worlds and their confrontation with one another require new ways of elaborating and analyzing creations. How do digital interfaces accompany mobility and how is mobility redefining these interfaces? What are the roles of digital interfaces in connecting someone to his or her spatial and social environment? What is the importance of spatial co-construction by several interacting subjects? The book is divided in three parts: 1) Game Devices: Game Narrative & Alternate Reality Games, 2) Devices, Medias and Technologies Analyses: Auditory and Movie Spaces; Scientific Issues and Intention Mining in Mobile Environments, 3) Artistic Issues: GPS Images, Cognitive and Aesthetic perspectives.