Mobile application markets are now transforming into a multibillion-dollar business. Understanding the consumer’s intention to purchase them and the moderating factors of individual differences – personality traits – allowed us to know more about consumers. The objectives of this research are to determine whether personality traits have any moderating effect with the consumer’s intention to purchase mobile application. Our preliminary data for the pilot study consists of 147 participants, who are office workers and students who use smart devices and live in Bangkok, Thailand. Hierarchical multiple regression was used to analyze the data. The results from our pilot study indicate that personality traits did not show a significant moderating effect. However, the result supported the original Theory Reasoned Action. It demonstrates that there are differences in attitudes toward the purchase of mobile applications between office workers and students. Therefore, this research has thrown up many questions in need of further investigation. As the initial data was only 147 respondents, a more extensive study will have to follow up our preliminary results.