The interest in the concept of “interactivity” has increased as we are entering an “always-on” society where people can interact anytime and anywhere. Despite the importance of interactivity in Mobile Commerce (MC) environment, this topic has been given little attention in the academic literature. This paper identified the components of interactivity and investigated the impact of perceptions of interactivity on customer trust and transaction intentions in MC. Empirical results indicate that the addition of MC-specific components of interactivity (perceived ubiquitous connectivity and perceived contextual offer) improves the model fit. Also the perceptions of user control, responsiveness, connectedness, ubiquitous connectivity, and contextual offer have a significant effect on customer trust in MC. Especially, ubiquitous connectivity and contextual offer have a direct positive effect on transaction intentions in MC. Based on these empirical results, this paper suggests managerial implications of new marketing strategies, focusing on the contextual marketing communication that link online, mobile, and offline environment.