A mobile health application for weight management and lifestyle modification: Development and usability assessment of Core 360

The present study focuses on the development and usability evaluation of Core360, a comprehensive mobile health application designed to support weight management and the adoption of a healthy lifestyle. The application integrates evidence-based components such as dietary guidance, physical activity tracking, hydration and sleep monitoring, mood assessment and motivational support within a single digital platform. Core360 was developed with an emphasis on simplicity, affordability, user engagement and scientific credibility to facilitate sustainable behaviour change. A short-term usability study was conducted among 21 young adults aged 18-25 years in Coimbatore to assess user experience, ease of navigation and motivational impact. Data were collected through in-app ratings, structured questionnaires and user feedback forms. The results revealed a high level of usability and acceptance, with 71% of participants rating the application as very easy to use, 100% reporting smooth navigation and 81% expressing overall satisfaction. The hydration tracker, calorie counter and motivational quotes were identified as the most valued features, contributing to enhanced engagement, self-monitoring and awareness. Notably, all participants reported improvements in mood and motivation within two days of application usage. The findings indicate that Core360 effectively meets its objectives of usability, accessibility and holistic health promotion. The study concludes that Core360 shows strong potential as an affordable, evidence-based mobile health intervention for weight management and lifestyle improvement. Further large-scale studies with long-term follow-up are recommended to validate behavioural outcomes and sustained effectiveness.