He received his Ph.D. in social psychology in 2003. His main interests are adolescents and their behavior on the Internet. David’s research focuses on online risks, identity development and its consequences in the virtual world, online communication, virtual romantic relationships and friendships, as well as addictive behavior on the Internet. He is the project head of the "World Internet Project: the Czech Republic", which is a part of the identically titled worldwide project. David is currently editor of “Cyberpsychology: Journal of Psychosocial Research on Cyberspace”.