Background: Considering the popularity of mobile health applications among people in the community and the positive results of studies, these applications can be helpful in improving and better controlling blood pressure in patients. Examining users' experiences using these technologies can enhance their effectiveness. Objectives: The current study aimed to investigate the experiences of pregnant mothers with high blood pressure using a mobile phone health application with a phenomenological approach in Kermanshah, Iran. Methods: This qualitative and phenomenological study was conducted in 2023. For this purpose, 17 pregnant mothers with high blood pressure were included in the study. Data were collected through semi-structured interviews and analyzed using the "Van Manen" method. Results: Four main themes and 12 sub-themes were identified from the interviews. Based on this, reliability (quality of content, educational method, and feedback), waiting time (no need to refer to different sources and speed of response), motivation (achievable goals, structure and order, encouragement and diversity in content), and facilities (interface easy to use, interactive activities and the ability to receive advice from an expert) were the themes and sub-themes extracted from the interviews. Conclusions: This study's findings shed light on the potential of mobile health applications for hypertensive pregnant women. They underscore the importance of user-centered design and the potential of mobile health applications to empower and support pregnant women with hypertension. Future research and innovation can lead to developing more appropriate and effective mobile health applications for individuals, thereby fostering a more optimistic outlook for healthcare by incorporating users' perspectives and needs.