This paper draws on qualitative data collected as a part of a comparative study on children and teenagers' uses of smartphone in nine European countries to explore the meanings and emotions associated with the enhanced possibility of "fulltime" contact with peers provided by smartphones. It argues that full-time access to peers -which interviewees identify as the main consequence of smartphones and instant messaging apps on their interactions with peers -is a communicative affordance, that is, a set of socially constructed opportunities and constraints that frame possibilities of action by giving rise to a diversity of communicative practices, as well as contradictory feelings among young people: intimacy, proximity, security as well as anxiety, exclusion and obligation. Understanding the perceptions and emotions around the affordance of "anywhere, anytime" accessibility, therefore, helps in untangling how communicative affordances are individually perceived but also, and more importantly, socially appropriated, negotiated, legitimised and institutionalised.