EtiquetAR is an authoring tool for supporting the design and enactment of situated learning experiences based on QR tags. Practitioners use etiquetAR for creating, managing and personalizing collections of QR codes with special properties: (1) codes can have more than one link pointing at different multimedia resources, (2) codes can be updated whenever needed without being reprinted and (3) multimedia resources linked through these codes can be commented by any user. This paper presents etiquetAR Mobile App, a mobile application that supports learners' interaction within spaces augmented with etiquetAR codes, offering responsive visualizations of the resources and mobile device adapted functionalities to add contributions. A pilot study with 95 students and 3 teachers illustrates the use of etiquetAR in a real learning activity. The results of this pilot indicate that etiquetAR App facilitates students' interaction with the tags having a positive impact on situated learning. [Funding for this work was also provided by EEE (Espacios Educativos Especulares) projects. For the complete proceedings, see ED557171.]