<![CDATA[Abstrak: Kemampuan visualisasi matematis merupakan salah satu kemampuan penting dalam memahami konsep geometri bangun datar, namun kemampuan tersebut masih tergolong rendah sehingga diperlukan media pembelajaran yang lebih interaktif dan inovatif. Penelitian ini bertujuan untuk mengembangkan aplikasi pembelajaran berbasis Android menggunakan iSpring yang memenuhi kriteria valid, praktis, dan efektif sehingga dapat meningkatkan kemampuan visualisasi matematis siswa. Penelitian menggunakan metode Research and Development (R&D) dengan model 4D yang dibatasi sampai tahap Develop. Instrumen penelitian meliputi lembar validasi ahli, angket respons guru dan siswa, serta tes pretest dan posttest. Hasil penelitian menunjukkan media memperoleh validitas 95% berkategori sangat valid, kepraktisan 100% dari guru dan 83% dari siswa berkategori sangat praktis, serta nilai N-Gain sebesar 0,57 berkategori sedang yang menunjukkan peningkatan kemampuan visualisasi matematis siswa. Dengan demikian, aplikasi pembelajaran berbasis Android menggunakan iSpring dinyatakan valid, praktis, dan efektif untuk meningkatkan kemampuan visualisasi matematis siswa pada materi geometri bangun datar serta layak digunakan sebagai media pembelajaran interaktif di tingkat SMP untuk mendukung proses belajar matematika. Kata Kunci: Android, iSpring, Geometri bidang, Keterampilan visualisasi matematis, Pengembangan media pembelajaran. Abstract : Mathematical visualization ability is crucial for understanding the geometry of 2D shapes; however, as current proficiency levels remain low, there is a need for more interactive and innovative learning media. This study aimed to develop an Android-based learning application using iSpring that meets the criteria of validity, practicality, and effectiveness to enhance students' mathematical visualization skills. The study employed the Research and Development (R&D) method using the 4D model, limited to the "Develop" stage. Research instruments included expert validation sheets, teacher and student response questionnaires, and pre-test and post-test assessments. The results indicated that the media achieved a validity score of 95% (categorized as "very valid"), practicality scores of 100% from teachers and 83% from students (categorized as "very practical"), and an N-Gain score of 0.57 (categorized as "medium"), demonstrating an improvement in students' mathematical visualization abilities. Consequently, the Android-based learning application developed using iSpring is deemed valid, practical, and effective for enhancing students' mathematical visualization skills regarding 2D shape geometry and is suitable for use as an interactive learning medium at the junior high school level to support the mathematics learning process. Keywords: Android, iSpring, Flat geometry, Mathematical visualization skills, Development of learning media. ]]>
