Mobile-Assisted English Vocabulary Learning: A Systematic Review of Platforms, Learning Outcomes, and Implications (2019-2025)

While mobile-assisted vocabulary learning (MAVL) has gained considerable scholarly attention, systematic synthesis of its platforms, learning outcomes, and pedagogical implications remains limited. This systematic literature review examined 36 empirical studies (2019-2025) to identify mobile platform types, analyse learning outcomes, and synthesise implications for research and practice. Following PRISMA guidelines, searches were conducted in Web of Science, Scopus, and ERIC databases using keywords including "mobile," "vocabulary," and "learning." Studies were screened using inclusion criteria specifying empirical research on mobile-based English vocabulary learning in ESL/EFL contexts. Thematic analysis was employed to categorise platforms and identify learning outcomes. Findings reveal six platform types, with game-based applications receiving the greatest research attention, followed by self-learning applications. Three learning outcomes are reported: enhanced word retention through spaced repetition, receptive and productive vocabulary development via multimodal input and interactive exercises, and increased motivation through gamification. However, deeper vocabulary aspects—including lexical organisation, collocation knowledge, and contextual usage—remain underexplored. Four implications emerge: research designs should incorporate longitudinal methodologies, applications require context-responsive features, vocabulary instruction requires multiple dimensions beyond breadth, and teacher facilitation is proven essential. Despite sample size and database limitations, this review provides evidence-based guidance for educators integrating mobile technology and researchers developing pedagogically informed vocabulary learning applications.