This randomized controlled trial aims to evaluate the impact of mobile application-supported education and counseling on the intention, attitude, behavior, and self-efficacy of pregnant women diagnosed with gestational diabetes. The study will be conducted at Ankara Bilkent City Hospital, with participants assigned to intervention and control groups. The intervention group will receive planned education and counseling via a mobile application, while the control group will receive standard hospital education. Data will be collected at predetermined intervals, and outcomes will be compared between the groups. The study seeks to determine the effectiveness of a mobile application-supported approach in the management of gestational diabetes.