Abstract
BACKGROUND: Pregnancy mobile health (mHealth) applications provide educational support to expectant mothers; however, usability challenges—such as complex navigation, culturally misaligned medical terminology, and concerns about clinical reliability—can limit user engagement and trust. This study aimed to address these gaps by evaluating a culturally tailored pregnancy health promotion app for Iranian users using a structured multi-level usability framework. METHODS: A three-level usability evaluation was conducted. Level 1 involved user-centered design assessment through focus groups with medical informatics experts and software developers, focusing on interface design, technical feasibility, and security. Level 2 comprised expert usability testing using think-aloud protocols with health specialists to identify interface, content, and performance issues. Level 3 involved real-world usability testing through a 10-day pilot study with pregnant women in their second or third trimester, using the user Mobile App Rating Scale (uMARS) and semi-structured interviews. Qualitative data were analyzed using conventional content analysis, while quantitative data were summarized using descriptive statistics. Findings across levels were integrated to generate comprehensive usability insights. RESULTS: Level 1 analysis identified four key themes: app design principles, user retention factors, web-based platform advantages, and security considerations, emphasizing UI/UX optimization and cross-platform accessibility. Level 2 revealed three themes: interface usability, content quality, and technical performance with recommendations for improved navigation, visual hierarchy, and loading speed. Level 3 demonstrated high user satisfaction in real-world use, with qualitative themes centered on information trustworthiness, cultural alignment, and interface simplicity. Quantitatively, the app achieved a high mean uMARS score of 4.2 out of 5.0, indicating superior usability quality. CONCLUSION: This multi-level mixed-method evaluation highlights the value of integrating expert and end-user perspectives to generate actionable usability improvements. By balancing technical robustness, user-centered design, and cultural relevance, the proposed framework offers a comprehensive approach for optimizing pregnancy mHealth applications and supporting maternal health promotion. CLINICAL TRIAL NUMBER: Not applicable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12911-026-03406-3.