This study explores the impact of mobile learning applications on the vocabulary acquisition, motivation, and engagement of Iraqi ESP medical students. This study was conducted with 60 students from Meisan University, who were randomly divided into an experimental group using the Quizlet mobile application and a control group following traditional vocabulary learning methods. To evaluate the effectiveness of the intervention, pretest and posttest assessments, including a vocabulary test, motivation questionnaire, and engagement questionnaire, were administered to both groups. The results demonstrate that the experimental group showed significant improvements in vocabulary acquisition, motivation, and engagement compared to the control group. These findings highlight the potential of integrating mobile learning applications in ESP contexts to enhance learning outcomes. The results of this study suggest that educators, syllabus designers, and policymakers should consider incorporating mobile technology into language learning strategies to foster more engaging and effective educational experiences.