The experiment presented here was suggested by our prior understanding of flow experience and the pilot study described in the previous section. To empirically investigate the research question described in Section 1, a simulated learning program, such as might be used for training security guards, was developed. This learning program was intended to allow trainee security guards to explore a physical space (or virtual space in the case of game-based learning) to become competent in securing specific premises. The pilot study showed that this navigation task in the building was challenging, so it could lend itself to flow experience. Three types of instructional design were developed to see the differences in both learning performance and flow experience; traditional map-based instruction (see Fig. 3), a game-based system (see Fig. 4), and a mobile learning system (see Fig. 5). The first (map-based) condition was regarded as a control condition, and the game-based system was built upon the assumption that game-based learning activities would present a highly engaging and immersive learning experience. However, this game-based system did not provide the same physical mobility as the real world, enabling us to consider the differences between virtual reality and reality when assessing flow experience in mobile learning.