Exploiting sensing devices availability in AR/VR deployments to foster engagement - Nicholas Vretos; Petros Daras; Stylianos Asteriadis; Enrique Hortal; Esam Ghaleb; Evaggelos Spyrou; Helen C. Leligou; Panagiotis Karkazis; Trakadas, Panagiotis; Kostantinos Assimakopoulos (Virtual Reality, 2019)