The authors conducted a needs analysis to investigate their medical students’ needs and preferences for using mobile devices for their English study. The analysis showed the students’ expectations of mobile learning were very high and two-thirds of them were interested in building medical English terminology through mobile learning. Then, the authors created mobile learning content designed mainly for helping their students review medical terminology. The content was delivered to 242 students twice a week during the period from July 2013 to January 2014. The authors then conducted a survey on their students’ perceptions of the content delivered. It revealed that half of the students found the content useful for their English study and about two-thirds of them found the content level to be appropriate. However, the log analysis showed that only an average of 9.5 % of the students worked on the medical quizzes. This result suggests that achieving a high degree of student involvement in their autonomous mobile learning is difficult and it is necessary for teachers to further investigate ways to enhance students’ motivation for mobile learning. Pages 172-178.