This study aims to analyze the contribution of Ruangguru application-based supervision to improving the professionalism of Islamic Religious Education (PAI) teachers at SMAN 1 Ciomas. The study focuses on digital literacy, reflective practice, teaching strategy improvement, and the supporting and inhibiting factors in digital supervision. This research used a descriptive qualitative approach with a case study design. Five informants were selected through purposive sampling, consisting of three PAI teachers, the vice principal for curriculum affairs, and the principal or academic supervisor. Data were collected through semi-structured interviews, limited observation, and documentation. The findings show that 100% of PAI teachers (3 out of 3 teachers) improved their ability to access, select, and integrate Ruangguru digital content into PAI learning. A total of 100% of PAI teachers also showed stronger reflective practice through the evaluation of student responses, digital exercise results, and supervisor feedback. In addition, 100% of PAI teachers improved their teaching strategies by combining direct explanation, learning videos, discussion, digital exercises, formative assessment, and Islamic value reinforcement. Furthermore, 80% of informants (4 out of 5 informants) stated that school support and supervisor feedback were the main factors supporting the success of digital supervision. The main obstacles included unstable internet access, differences in teachers’ digital competence, limited time, and insufficient supervision follow-up. This study concludes that Ruangguru-based supervision can serve as a professional development model for PAI teachers when implemented in a structured, reflective, and sustainable manner.