The provision and active trading of diverse applications can be a critical factor for the success of not only the application market but also the smartphone industry. Accordingly, this study examined consumer behavioral patterns in the application market, and particularly investigated consumers' attitudes toward and the influence of online word-of-mouth (WOM) information, which significantly affects application purchases, by differentiating based on cultural differences (Korea and the United States). This study focused specifically on consumer ratings among online WOM information, because existing studies examining the relationship between consumer ratings and sales performance have not produced consistent results. One of the causes of these mixed results may be consumer characteristics arising from different cultural backgrounds. Therefore, this study investigated the impact of consumer ratings on consumer purchasing behavior, particularly application sales performance, through empirical analysis while considering such cultural differences. For the empirical analysis, data were collected on the download counts and consumer ratings provided by the App Store for the 50 most downloaded applications in the U.S. App Store and the 50 most downloaded applications in the Korean App Store during the month of September 2012. The analysis results showed that Korean consumers and American consumers have different attitudes toward online WOM information, and specifically, consumer ratings had a greater influence on Korean consumers' application purchases compared to American consumers. The theoretical and practical contributions of this study are as follows. First, while existing smartphone research has primarily focused on technical aspects, this study is one of the few to approach the topic from the consumer perspective by identifying factors influencing application purchases, and it is particularly significant in that it used actual application download counts to analyze factors affecting application purchases. Second, it is meaningful in online WOM research in that it revealed that consumer ratings are a factor influencing application purchases, and that variables such as consumer characteristics must be considered to clearly identify the impact of consumer ratings on sales performance. Finally, it provides practical implications for companies engaged in the smartphone business and application developers.