Research on dynamic assessment (DA) has been conducted on the efficiency of either face-to-face (F2F) or mobile-assisted (MA) DA sessions. However, studies investigating the difference between these sessions conducted in the foreign language learning context are scarce. Thus, this study aims to explore the differences between F2F- and MA-DA sessions in terms of the mediator's mediational moves and learners' reciprocity behaviors. To this end, F2F- and MA-DA sessions were held with four tertiary-level learners. Then the mediational moves and reciprocity behaviors employed in these sessions were explored through qualitative descriptive analysis. The results showed that the DA interactions between the mediator and the learner in F2F and MA contexts were generally not much different in terms of the mediational moves and reciprocity behaviours. However, it is noteworthy that the learners made more inaccurate responses and used L1 more in F2F-DA sessions. In contrast to this, the learners made more careful attempts in MA-DA sessions. Moreover, the teacher as a mediator tended to give more approval to the learners' responses to eliminate the disadvantage of the restricted context of MA-DA. In light of these findings, pedagogical implications were suggested for both language teachers and researchers.