Fragkiskos Gryllakis is a PhD Candidate at the Department of Informatics, University of Piraeus. Prior to this, he received his MSc in Advanced Information Systems from University of Piraeus, his first BSc in Economics from Aristotle University of Thessaloniki and his second BSc in Computer Science from Athens University of Economics and Business. His research interests include graph databases, spatio-temporal-textual data management and analytics, big mobility data management and analytics, semantic trajectories and community detection.