This study explores the use of language learning apps as a didactic tool for vocabulary building in an English as a Foreign Language (EFL) context. It was developed through a mixed-methods approach, with a concurrent design in order to collect, analyze and validate qualitative and quantitative data. Although there was controversy on the use of technology in the classroom in the rural context where this study was developed, it advocated for practices that could go beyond the classroom boundaries and that were part of students' lives and social realities. The participants were 20 high school students and the intervention was during a six-month period. The data collection instruments included an initial diagnosis and a final development test, eight lessons and eight assessment sessions using language learning apps (Duolingo and Kahoot), eight entries to a research journal and a final survey. In the end, it was possible to provide evidence of the way technology and classroom practices can be allied to effectively foster vocabulary building.