This article suggests an incursion into the concept of digital materiality in order to reconfigure the theoretical and methodological perspective in the study of social practices that are part of the social media activity. Drawing on the fieldwork carried out in two letters writing campaigns to “political prisoners" in Brazil and Catalonia, the analysis focuses on the letters and their circulation as the axis of the activist campaigns, expanding the concept of digital ethnography to include fieldwork that takes place in social media as well as in villages and squares. This approach decentres the digital and its social impact as the focus of inquiry to examine the role of social media as part of a wider political action.