The focus of this thesis is usability of an everyday used product; the cell phone seen from a Human – Computer Interaction perspective. The purpose with the thesis is to create an understanding of how cell phones are used by persons in natural /public settings and in everyday activities. Further the purpose is to describe users’ experiences of using cell phones. In this study, ethnography was used as method. The theoretical framework is the contextual usability perspective. The cell phone is used in many contexts and in different ways. We can make the conclusion from what the study shows, that the cell phone is outermost used and need for social issues. From a subjectivity perspective on usability, we can see that the cell phone is a product which needs and goals are highly subjective to the user. From a flexibility perspective on usability, we see that the cell phone is used in different contexts and therefore must be flexible in use. From a subjectivity perspective on usability, we see that it is a product that exists and is used in a social environment. A design suggestion that correspond to these aspects is the module cell phone. We can also make the conclusion that goals, needs and use are inseparable and constitute prerequisites for each other.