Smart Diet Diary: Design and Development of a Mobile Application for Child Nutrition Guidance in Tanzania

Abstract

Child undernutrition remains a major public health challenge in Tanzania, with stunting affecting approximately 34% of children under five. Limited access to nutrition professionals, geographic barriers to health services, and inconsistent caregiver knowledge constrain access to age-appropriate dietary guidance. This study developed Smart Diet Diary, a mobile application designed to support nutrition guidance for children under six by enabling registered nutritionists to publish age- and weight-based dietary plans accessible to parents and caregivers. A Design Science Research approach was adopted, with requirements gathered through semi-structured interviews with five nutritionists from four hospitals in Dar es Salaam and informed by a narrative review of World Health Organization infant and young child feeding guidelines. The application was developed using Flutter/Dart, PHP, MySQL, and a REST API. Validation included functional testing of all core requirements and a User Acceptance Test involving 20 participants, yielding mean usability and acceptability scores ranging from 4.4 to 4.7 out of 5. The findings demonstrate the technical feasibility and preliminary user acceptability of the application as a nutrition decision-support tool. However, no clinical or behavioural outcomes were assessed; further large-scale usability and impact studies are required before broader deployment.

Keywords: Child undernutrition; mobile health (mHealth); nutrition decision support; caregiver guidance; usability evaluation; Tanzania