Abstract
This study is aimed to assess the impact of Memrise and Duolingo on vocabulary acquisition language learners. Students used both applications for 4 weeks daily, accomplishing four modules in Duolingo and four levels in Memrise. A quasi-experimental approach was used, including pre- and post-test to assess the level of vocabulary proficiency, memorization and engagement. The results showed significant improvements in vocabulary proficiency by all participants, with obvious benefits noted for each application. Memrise succeeded in memorizing vocabulary using mnemonic techniques, while Duolingo promoted greater engagement and practical use of the language and selected as preferred application. The comparison highlights the complementary advantages of both platforms and suggests their joint use to achieve maximum results in learning vocabulary. This research provides teachers and language learners with evidence-based information and helps optimize language learning strategies using mobile devices. Both applications prove to be significant resources for lexicon acquisition, with Duolingo emerging as the preferred tool due to its engagement and versatile features. However, the choice of the preferred application should depend on individual needs, preferences and learning goals. Keywords: Memrise, Duolingo, EFL learners, English, vocabulary, mobile-assisted learning, applications, technology-assisted learning.