This study investigates the difference between popular genre of mobile games and that of online games, and also the impact of affiliation with social network platform on the market performance. The results show that three genres such as action, puzzle, and RPG occupy a higher market share than the other genres. The structure of the mobile game market is more competitive than that of the online game market but game applications developed by top four developers - CJ E&M, NHN, com2us, WeMade - have been holding high ranks for months. It implies that the structure of the mobile game market is gradually becoming more concentrated. As the market competition increases, the marketing cost for acquiring recognition and the commission fee paying for platform have been increasing accordingly. Consequently, mobile game developers are encouraged to enhance the quality of their games as well as to devise diverse platform-marketing strategies in order to accomplish stable market performance.