The frequent use of mobile communication devices can be observed in the daily life and generates implications in different fields, among them in Education. This research aimed to identify the perceptions of university students about the use of these devices, specifically mobile phones, in study activities, in dialogue with theoretical references of socio-historical psychology, focusing on the relations between communication and cognition. In the development of the research, we also seek: to describe the main ways of using the mobile phone in study activities; to understand the motivations for identified uses; to verify the earnings perceptions related to the performance of study activities using the devices; to identify if there are differences of uses and visions among students of STEM (Science, Technology, Engineering and Math) and students of Humanities and Social Sciences. As a qualitative study, the research had as methodological procedures the application of semi-structured interviews to 20 students from six undergraduate courses of the Federal University of the State of Rio de Janeiro (Unirio) and the content analysis of each one of them. The data produced indicate that students value peer-to-peer learning mediated by mobile communication devices and recognize gains in interactions that occur in virtual environments. On the other hand, they point to the use of these devices as a source of distraction or escape in situations uninteresting, annoying or uncomfortable in the classroom; and they have the expectation that their teachers play an active role in proposing activities that use mobile devices as a pedagogical resource.