It is widely believed that mobile clinical information systems can facilitate patient care, increase treatment capacity, reduce healthcare costs, and improve efficiency. Yet, there is limited research to substantiate these claims in healthcare delivery settings, partly due to lack of widespread adoption and use. This study summarizes our results on the adoption and usage trends in a community hospital which deployed several mobile clinical applications for daily patient care. We analyze twenty-two months of usage data to understand trends in physicians’ adoption and use of specific mobile applications. Applying a novel, semi-parametric, group-based, statistical methodology, we obtain developmental trajectories depicting how usage evolves from initial ‘trial’ adoption to long-term institutionalization. We examine this longitudinal developmental pattern to understand how users can be clustered and profiled, and provide insights indicating that the potential impact of social influence needs to be further explored to develop new approaches to facilitate adoption.