According to Palácios and Cunha , six fundamental properties characterize the spaces of journalistic information online nowadays: hypertextuality, interactivity, multimediality, personalization, continuous updating and memory.
Smartphones and tablets led to the emergence of a new element that is added to the above characteristics: tactility. In the point of view of the two referred authors, tactility is an important new characteristic of mobile communication devices and presentation of journalistic information that must be researched and tested.
This research intended to establish a dialogue with different theoretical views addressing the interaction between people and computers. The predominant and canonical theories of HCI are commonly knowledge based (Preece et al., 2002) . Its roots came from cognitive psychology, cognitive sciences and artificial intelligence - disciplines that study cognition (the process by which one can acquire knowledge). They seek to understand the mental constraints of the users during their interaction with interfaces. On the other hand, there are also semiotic approaches to Human Computer Interaction - whose theoretical basis, Semiotics, is the discipline that studies signs, semiotic systems and communication. These were related to the work of semioticians like Charles Peirce, Jakobson and Umberto Eco.
In order to understand the applicability of systems, we decided to work with both the concept of usability (from the knowledge-based theories) as well as with the concept of communicability (by Semiotic Engineering).
Usability refers to the quality of system interactions with its users and includes several aspects such as ease of learning and use, user satisfaction and productivity, among others. On the other hand, communicability describes the property of a system to transmit to the user, in an appropriate manner, intentions and interaction principles that guided its design.
In the Semiotic Engineering (SE) point of view (De Souza et al., 1999) , the system interface is a message sent from the designer to the user. The designer is the author of this message transmitted to the user, and the Human-Computer Interaction reflects this meta process. Thus, interface design involves not only the intellectual conception of a system model, but also the communication of this model.
In semiotic approach, user interfaces can be viewed as one-shot, higher-order messages sent from designers to users. The content of such messages is a designer’s conception of who the users are, what their needs and expectations are, and, more important, how the designer has chosen to meet these requirements through an interactive artifact. The form of the messages is an interactive language. As Prates, De Souza and Barbosa  suggested:
In parallel with software usability, we can then assess software communicability. Communicability is the property of software that efficiently and effectively conveys to users its underlying design intent and interactive principles .
It’s important to add the work of Cavallo and Chartier  in our research: the historical foundation for understanding how tablet revolution can explain changes in reading practices. History of reading practices considers the “text world” as a world of objects, forms and rituals, with conventions and specific arrangements that lead the construction of meaning. Therefore, there is no text outside the support that provides the reading: authors do not write books, write texts that become written objects - manuscripts, engravings, printed or computerized -, handled differently by readers of flesh and blood.
Thus, Cavallo and Chartier stand against the representations of common sense in which the text exists in itself, apart from its materiality.