The Growth and Nutrition Monitoring System (GNMS) is an innovative project in Sri Lanka’s public health system that utilizes mobile devices for data collection in the field. It is designed as an electronic-based individual information tracking system specifically focused on monitoring malnourished children at the grassroots level. The GNMS employs Android-based individual tracker software installed on mobile devices used by Public Health Midwives (PHMs) who enrol malnourished children detected through anthropometry at weighing points. These PHMs regularly enter anthropometric measurements during subsequent clinic visits to track the children’s progress. Additionally, PHMs conduct in-person visits to the households of these children to assess household-level risk factors for malnutrition using a standardized questionnaire. The collected data is then entered into the software. The identified household risk factors are classified into two categories: health and non-health. Children with health-related risk factors are referred to nutrition clinics for appropriate interventions. In contrast, non-health risk factors are communicated to relevant officers of a five-member village-level committee. This committee, formulated under the Multi-Sector Action Plan for Nutrition (MSAPN), includes Public Health Midwives, Economic Development Officer, Agricultural Officer and many more. The committee members are responsible for implementing suitable interventions based on the identified non-health risk factors.Continuous monitoring of the nutritional status of these children through regular follow-ups by the PHMs. The progress of non-health interventions is expected to be monitored by other village committee members. To facilitate the implementation of the GNMS, PHMs are provided with smartphones on which the GNMS Android application is installed from the Google Play Store.The application features trilingual interfaces, supports GPS-based location information, and provides realtime validation of collected data using nutritional colour coding. It also incorporates familiar interfaces similar to the existing paper-based system. The software assists field-level health workers by offering longitudinal charting of data and graphical analysis through various built-in charts. Moreover, it supports offline data entry on a local database, synchronized periodically with the data warehouse. This feature is particularly essential for capturing field-level data in Sri Lanka. The GNMS utilizes the DHIS-2 platform, which is currently used by other public health-related information and surveillance systems. This interoperability enables seamless data exchange across these systems, offering additional advantages to the GNMS software.