Abstract
Mobile learning has been widely applied in language learning. However, empirical evidence regarding its use on vocabulary development remains limited. This study employed Rain Classroom, an interactive blended-learning tool, to provide tailored vocabulary support for college students with varying levels of English proficiency. 50 first-year college students were recruited and stratified into three groups (low, intermediate, and advanced) according to their English proficiency. The participants took part in a one-semester English vocabulary intervention delivered via the Rain Classroom mobile application. Three vocabulary quizzes were administered via Rain Classroom at the beginning, middle, and end of the practice to assess students’ vocabulary acquisition during the study. After the intervention, students completed a questionnaire regarding their perceptions of vocabulary instruction and their acceptance of Rain Classroom. The results showed that all groups made progress in their vocabulary learning, with the intermediate- and low-English-level groups showing notable improvement. The majority of students reported satisfaction with their English vocabulary development using Rain Classroom. The findings suggested potential benefits of implementing mobile applications in English vocabulary instruction to enhance EFL learners’ English proficiency in similar contexts.