BACKGROUND:Use of herbal medicines is common. There is a need for education in this area. Mobile games are useful educational tools for motivating learning. A mobile game on herbal medicines can potentially enhance players' herb-related knowledge. Our objective was to develop a mobile game to motivate players to learn more about herbal medicines. METHODS:Game development comprised of storyboarding, user interface design, database development, server development and distribution. A pilot usability study was conducted for the game prototype. Data was gathered through user registration, background data collection and a post-game survey containing a quiz on herbs encountered in the game. Mann-Whitney U test, chi-squared test and Spearman's correlation coefficient were used for data analysis. RESULTS:"Herbopolis" is an in-house developed mobile game of the simulation genre. Players are tasked to manage a city specializing in the production and sale of herbal products. Nineteen out of 24 participants downloaded and played the game, and completed the post-game survey. Heuristic evaluations for usability, playability and educability were generally positive. Strong positive associations were observed between player level (r = 0.810, p < 0.001) and gameplay time (r = 0.757, p < 0.001) with quiz scores. Female players scored higher in the quiz (p = .044), played for more days (p = .010) and attained higher levels (p = .010) than male players. CONCLUSION:Players are motivated to learn about herb-related information through playing "Herbopolis". Our results support its use for improving knowledge on herbal medicines. Future game iterations to improve robustness and performance will likely to improve its reception and effectiveness in learning.