Thirteen years since the first iPhone: A systematic review on the effectiveness of language learning apps on smart devices

Powered by advanced calculating power and novel technologies like artificial intelligence, smartphone apps offer unprecedent creative solutions in education. They have the potential to change the reality of language teaching and learning. This systematic review critically evaluates the empirical basis for the effectiveness of language learning apps. A rigorous search on electronic databases and two screenings identified 32 eligible studies, mostly with adults and learners with lower levels of proficiency. The research comprises of two types of comparisons: one compared the effectiveness of different apps or versions of the same app; the other compared language learning apps with other methods of language learning. The research covered a dozen countries, nine languages, nine language skills, 10 commercially available apps and a larger number of researcher-developed ones. 25 of 32 studies found unequivocally positive effects of learning foreign language on apps regardless of functions. Such features as gamification and adaptive learning are conducive to improving language proficiency. Only two studies found participants to score either lower or equally after treatment. A risk of bias assessment reveals that the overall quality of research is low due to inadequate study design and reporting practices. For language learners, apps can provide affordable and accessible educational resources. However, there is insufficient evidence to show that learners of all ages and proficiency levels benefit equally from apps. Future research needs more robust study designs and should direct attention to study non-adult learners, more advanced learners, and languages other than English.