Tabriz University of Medical Sciences Health Promotion Perspectives 2228-6497 16 1 2026 06 06 What Makes Mobile Banking Difficult for Older Adults? A Multi-Layer Usability Investigation 74 84 10.34172/hpp.44884 EN Elahe Amouzadeh https://orcid.org/0000-0002-8318-0195 Iman Dianat Javad Faradmal Maryam Khalili Mohammad Babamiri https://orcid.org/0000-0002-0824-8567 Journal Article 10.34172/hpp.44884 2025 06 20 2025 12 26 Introduction: This study evaluates the usability, accessibility, and ergonomic design of six widely used Iranian mobile banking applications for older adults (aged 60 and above) to enhance digital inclusion and promote healthy aging through improved financial access. Methods: An explanatory sequential mixed-methods approach was utilized, integrating quantitative usability testing with the System Usability Scale (SUS) and qualitative heuristic evaluation using the Smartphone’s Usability Heuristics (SMASH) framework. Five Human-Computer Interaction (HCI) experts evaluated the applications in a controlled lab setting, while 1,200 older adults from diverse backgrounds participated in usability testing and semi-structured interviews. Statistical analysis involved ANOVA with post hoc Least Significant Difference (LSD) tests to compare SUS scores across applications and age groups, complemented by thematic analysis of qualitative data. Results: Heuristic evaluation identified 135 usability issues, with error prevention (mean severity: 2.27) and visibility of system status (mean severity: 2.22) being the most critical. SUS scores varied significantly (F(5, 1194)=42.36, P<0.001), ranging from 27.50 (SD=7.18) for Bank E to 59.02 (SD=7.94) for Bank A. Younger older adults (60–63 years) reported higher SUS scores (M=54.2) than those aged 72–75 (M=45.3, P<0.001). Qualitative findings highlighted cultural mismatches and cognitive overload as key barriers. Conclusion: Poor usability in mobile banking apps widens the digital divide for older adults, hindering financial independence. Tailored designs with simplified interfaces, cultural relevance, and enhanced error prevention can improve digital health literacy, support equitable access and promote mental and social well-being among aging populations.