OBJECTIVES: Ghana’s Expanded Program on Immunization reports aggregate data and uses paper-based registers which are inadequate at service delivery points. Individualized child level data are not available for healthcare decision making. This study aimed to develop web and mobile-based outreach vaccination application to track children to improve coverage and system efficiency.   METHODS: We authored paper forms into digital forms using XML editor, set-up aggregate server for data storage retrieval and created mobile application for field data collection. Traditional paper vaccination records were modified to include epidemiological, geospatial, and photographic data fields. These were digitalized into an Android app named mVaccine. The mVaccine app was developed from Open Data Kit (ODK) source code. The complex forms were programmed into XLSForms supported by Javarosa. MySQL web server with Apache Tomcat was set up to receive and host blank digital forms developed for vaccination data collection. The same code base that runs on local server backed with MySQL will run on Google App Engine or Amazon Web Services. Blank forms uploaded onto server automatically generate MySQL database tables ready to receive submitted data from mVaccine App.  RESULTS: We developed web-based Smartphone app (mVaccine) that collects socio-demographic, epidemiological, vaccination, geospatial and photographic data of vaccinated children to improve vaccination coverage and reduce drop-out rates. It has the capacity to remind parents of vaccination schedules. Mobile devices with mVaccine installed are synchronized with the server for bidirectional transactions. Data submitted from app is stored in the MySQL database online. The app does not require internet connectivity to operate except to submit Completed forms.  Submitted data generate spreadsheets, geospatial maps and charts of vaccination performance indicators. The app also determines performance of healthcare workers and therefore serves as monitoring tool.  CONCLUSIONS: Undoubtedly, this innovation has the capacity to transform vaccination programs in low resourced settings, as it will improve efficiency and performance.