Access to body-based resources has been shown to augment cognitive processes, but not all movements equally aid reasoning. Interactive technologies, like dynamic geometry systems (DGS), potentially amplify the link between movement and geometric representation, thereby deepening students' understanding of geometric properties. This study investigated the influence of access to a DGS on students' geometric reasoning and gesture production compared to the impact of only spontaneous gestures. Access to simulations did not significantly increase the likelihood of students producing correct mathematical insights compared to spontaneous gestures. However, when controlling gesture production, DGS access became a significant predictor for transformational proof production. We also found that access to DGS influenced the type of gestures students produced during geometric reasoning tasks. This study underlines the vital role of gestures in geometric reasoning and suggests that while DGS offers benefits, spontaneous gestures remain a crucial embodied resource for exploring geometric concepts. [This paper was published in: "Proceedings of the 18th International Conference of the Learning Sciences - ICLS 2024," edited by R. Lindgren et al., International Society of the Learning Sciences, 2024, pp. 131-38.]