Postpartum mental health is a common concern in modern society, but many women struggle to access adequate support. This study aims to propose an inclusive design framework for a mobile application for postpartum emotional support. The user’s needs and expectations were extracted from the app reviews using the Non-negative Matrix Factorization (NMF, Non-negative Matrix Factorization) technique, which is widely used in the field of data mining and pattern recognition, and were combined with a tool for evaluating and optimizing the characteristics of a product or service: the Importance-Performance Analysis (IPA, Importance-Performance Analysis) model to explore the association between perceptions and expectations of postpartum women. As a result of the analysis, six key quality elements were identified and four areas of design and development were suggested. The core innovation of this study is the introduction of an IPA analysis method based on the NMF algorithm, which enhances the design and development of the application to ensure that a wider range of user needs are met. This not only facilitates the inclusive design of mobile applications, but also enhances the decision-making ability of new mothers in online mental health services.