PurposeThis study offers an understanding of vulnerable populations' experiences of actual use of mobile banking and their expectations of mobile banking (MB).Design/methodology/approachData were generated from MB customers and bankers using online reviews, focus groups and semi-structured interviews, as a mix of methods and sources can provide rich and in-depth understanding.FindingsThe affordance of MB for vulnerable populations is explained in four concepts: meaning, material, competency and usability. Recommendations that could further engage and improve the service quality of MB apps for vulnerable populations include customization and personalization of services, access to the digital health data of members of vulnerable populations, audio-based option selection and touchscreen options, and enhancement of service and performance standards.Research limitations/implicationsIt is suggested that retail bankers should improve the service quality and performance of their MB apps by considering the recommendations drawn from vulnerable people's experiences. This study discusses implications for retailers.Originality/valueThis study applied social practice theory and affordance of technology theory to understand how those in vulnerable populations experienced MB apps; the results could be used to improve the accessibility, performance and service quality of MB apps.