The mobile communication of children and teenagers has spread rapidly. For their generation, mobile communication has become a fixed and stable part of life. Children and teenagers use mobile terminals differently to adults, and gender and age differences create different use. Mobile communication is often connected with cross-media surfing: e.g. Internet, e-mail and IRC-channels. The University of Tampere has studied the mobile communication of under 18-year-olds since 1997. The cultural research conducted is based on qualitative methods.