Smartphone-based experimental exercises were incorporated as part of the homework problems in an introductory mechanics course at a university. A quasi-experimental field study with two cohorts design was performed to measure the impact of such exercises on motivation, interest and conceptual understanding. The empirical results on learning achievement show a significant positive influence of the smartphone-based experimental exercise for the dynamics of rigid bodies topic with a medium effect size of d = 0.42. For the analysis of rotational motion topic, a positive learning achievement for both groups was evidenced, but the effect size of the smartphone-based exercise was rather small at d = 0.20 . The intrinsic and germane cognitive loads turned out to be similar at an intermediate level for both groups. However, the extrinsic cognitive load for the intervention group decreased significantly, which might be the reason why more complex experimental exercises foster conceptual understanding.