In this paper, we argue that in order to gain a deeper understanding of collaborative mobile learning in schools, it is important to know not only how mobile devices affect collaborative learning but also how collaborative learning emerges and is mediated by these devices. We develop our argument by applying the instrumental genesis theory and the collective instrumented activities and situations model for the analysis of learners' collaborative learning in the tablet-mediated classroom. This analysis is grounded in data collected in four elementary Swedish schools (i.e., from fourth to eighth grade). From the data, we considered the learners' conversation in English as a foreign language, inquiry-based learning in the natural sciences classroom and game-based learning in the arithmetic classroom. On the one hand, the scrutiny of these specific activities led us to distinguish the pragmatic, epistemic, and reflexive instrumental mediations that have already been theorized in the instrumental genesis theory. On the other hand, they helped us to identify two additional ones, which we call emotional and spatial. Based on these findings, we claim that collaboration in the tablet-mediated classroom is a complex activity that emerges from a variety of instrumental mediations that configure contemporary collaborative mobile learning.