This study aims to evaluate the effectiveness of a mobile health (mHealth) educational intervention for adolescents with Type 1 Diabetes Mellitus (T1DM). Adolescents often face challenges in maintaining optimal blood glucose control and performing regular self-care. In this study, participants will receive structured diabetes education through a mobile application designed to improve their knowledge, self-efficacy (SE), and self-management skills. The impact of the intervention will be assessed by measuring changes in HbA1c levels, diabetes self-efficacy, and self-care (SC)behaviors over time. These findings may help determine whether mobile app-based education can support better diabetes management among adolescents.