The increasing penetration of smartphones among global population, especially among youth and children, has define a mobile and interactive media use without any precedent. A global connected world is the context in where our offspring are developing self-competences in media literacy because they manage technological devices at very early ages. This context is the state of affairs of this article in which we present two different steps: firstly, a theoretical study, showing the impact of mobile devices, focusing on smartphones and mobile applications where the question arisen is: What are children and young doing while online? Media literacy is also described in order to apply its dimensions to the empirical study. Secondly, we present a pilot study in a sample of 140 students aged from 10 to 13 focusing on the access to mobile apps, and social network access and use. This research is based on the hypothesis that Primary School students, from 9 to 13 years old, are massive users of some specific social networks that are providing them abilities, skills and competences from a media literacy needed in the 21st century.