Antenatal Care (ANC) service performed by midwives in Primary Health Care (PHC) became more efficient through mobile health (mHealth) implementation. However, no work has yet been conducted toward the development of the technologies for integrating the service since midwives provide not only in-house clinic service but also community works such as home visit and site clinic. The objective of the study was to design a mobile health application using user-centered needs approach to consider the functionality and usability of the users. We conducted a case study in South Tangerang, an urban city of Banten Province, Indonesia using in-depth interview for prospective users and collected usability testing of mock-up mobile application through System Usability Scale (SUS) among 20 respondents. Functional features were identified namely: 1) pregnancy register such as personal identity, spouse identity, and ANC content, 2) pregnancy monitoring such as high-risk pregnancy, diagnosis, and maternal status. As conclusion, this is the first study to design a mobile Health for integrating ANC service based on UCD framework. The study indicates that UCD is found as useful guidance for designing a monitoring and registration mHealth application named SIMORI for integrating ANC service in primary health care.