Electronic and web technologies include a significant economic and social force in contemporary life and business. Commercial activities conducted over computers and mobile networks empower business processes and add value to consumers by introducing unique channels for buying and exchanging information. Whereas past research expanded knowledge about attitudes and perceptions toward e-commerce that drive consumer purchase intentions and provide a competitive advantage, the fundamental behavioral dynamics associated with m-commerce requires further investigation. Based on the unified theory of acceptance and use of technology (UTAUT), this quantitative, survey-based study investigates adult American users of m-commerce to measure their perceptions of performance and effort expectancies, social influence, the facilitating conditions of m-commerce trust and perceived risk. This study surveyed 177 participants to measure their perceptions of performance and effort expectancies, social influence, the facilitating conditions of m-commerce trust and perceived risk, and their m-commerce purchase intentions. The results of this study indicated that performance and effort expectancies, social influence, and the facilitating conditions of trust and perceived risk in the use of m-commerce together predicted m-commerce purchase intentions at a statistically significant level regarding competitive advantage.