Recent technological advances in telecommunications and information technology have provided the emergence of several new instruments of social communication. These innovations have created the so-called social networks and various mobile vehicles of instantaneous communication. This study aims to identify the reasons why WhatsApp has excelled in this sector, particularly in Rio de Janeiro. To achieve this objective a bibliographic research and pieces of field research involving four focus groups were conducted. The method is based on the construction of perceptual maps by using a qualitative approach. As participants classify the twelve selected media outlets, they report their views in relation to each of them, revealing gradually the reasons why use one or the other. Once achieved a degree of consensus among the participants they are submitted to a questionnaire that identifies their demographic profile and reinforces specific questions about using WhatsApp. The results suggest that, in addition to being perceived as a complete communication tool. regarding its text, sound and images exchange capacity, this instrument is the most widely adopted by their acquaintances, either friends, member of family or co-workers. The answer on how WhatsApp has become the most widely used application, however, requires further studies.