JURNAL PENDIDIKAN DAN PENGAJARAN Volume 55 Nomor 3 2022, 469-479 E-ISSN: 2549-2608; P-ISSN: 2301-7821 DOI:https://doi.org/10.23887/jpp.v55i3.40661 469 Android-Based Mobile Application for Vocabulary Learning Hesty Puspitasari 1* , Ruth Febry Maharani 2 , Wawan Herry Setyawan 3 , Yusniari Primasari 4 1,2,4 English Education Department, Balitar Islamic University, Blitar, Indonesia 3 English Education Depatment, Universitas Islam Kadiri, Kediri, Indonesia *Corresponding author: hestypuspita1403@gmail.com Abstrak Kemajuan teknologi telah membuatnya tak terelakkan untuk digunakan dalam belajar kosa kata. Tidak dapat disangkal bahwa gaya belajar mempengaruhi penggunaan aplikasi. Oleh karena itu, penelitian ini bertujuan untuk menganalisis kemanjuran aplikasi mobile berbasis android untuk pembelajaran kosakata pada pelajar kelas sepuluh. Pada titik ini, produk tersebut adalah aplikasi mobile untuk belajar kosa kata yang dilengkapi dengan buku guru dan siswa untuk panduan belajar. Peneliti menerapkan Research and Development dengan 20 siswa dan 5 guru sebagai partisipan penelitian secara acak dari dua SMA. Instrumen yang digunakan adalah tes, pedoman wawancara, pedoman observasi, dan angket. Proses pengumpulan data secara sistematis mencari dan menyusun transkrip wawancara, catatan lapangan, validasi ahli dan bahan-bahan lain yang dikumpulkan untuk mendukung data yang ditemukan. Kemudian peneliti menganalisis data menggunakan triangulasi data. Hasil dari langkah pertama membuktikan bahwa kemampuan pemecahan masalah diperoleh siswa memiliki banyak kesulitan mengingat kata-kata asing dan menguasai arti kata-kata asing. Hasil perancangan dan pengembangan menunjukkan bahwa Aplikasi Mobile sudah valid. Hasil uji coba produk membuktikan bahwa bentuk ini layak diterapkan pada siswa dalam peningkatan kosakata dan diklaim bersumber secara umum. Sedangkan hasil uji produk bahwa produk berpengaruh penting terhadap kosakata siswa. Media “Aplikasi Kosakata” meningkatkan kosakata siswa. Kata Kunci: Aplikasi Seluler, Belajar Kosakata, Vocabulary Application (VocApp) Abstract The improvements in technology have made it inevitable to use in learning vocabulary. It is an undeniable fact that learning styles affect the use of applications. Accordingly, this study is aimed to analyze the efficacy of mobile applications based on Android for learning vocabulary to tenth-level learners. At this point, the product is a mobile application for learning vocabulary completed with teachers’ and students’ books for learning guides. The researchers apply Research and Development with 20 students and five teachers as research participants randomly from two Senior High Schools. The instruments used tests, guiding interviews, guiding Observations, and questionnaire. The process data is collected by systematically searching and arranging the interview transcript, field notes, validation expert, and other materials you accumulate to support the data found. Then the researchers analyze data using triangulation data. The results of the first step prove that problem-solving abilities are shown; students need help remembering unfamiliar and mastering the meaning of foreign words. The result of the design and Development indicates that the Mobile Application was valid. The results of the product experiment prove that this form is appropriate to be applied to students in vocabulary upgrading and is claimed to be sourced in general. At the same time, the product test result shows that the essential has an important effect on students’ vocabulary. The “Vocabulary App” media improves students' vocabulary. Keywords: Mobile Application; Learning Vocabulary; Vocabulary Application (VocApp) History: Received : August 20, 2022 Revised : August 23, 2022 Accepted : October 12, 2022 Published : October 25, 2022 Publisher: Undiksha Press Licensed: This work is licensed under a Creative Commons Attribution 3.0 License 1. INTRODUCTION Along with other components like structure, pronunciation, and tone, vocabulary is one of the most critical aspects of teaching English. If a student's vocabulary is limited, he will be unable to clearly explain their thoughts and ideas, both orally and in writing (Janebi Enayat & Derakhshan, 2021; Sun & Dang, 2020; Wang, 2017). Similarly, limited talents will limit listening and reading capabilities. If language is the body, the form is the bone that creates the framework, whereas vocabulary or speech is the flesh that creates the bodily form (Harmer, 2001; Somdee & Suppasetseree, 2013). If a person's code skill meets the requirements, he or she can able to communicate in the target language. From the above