•We analyse how SMEs in developing economies use mobile apps to improve their business efficiency during the pandemic.•The study recognizes effective measures and actions taken by SMEs that have turned to mobile-app-based business to improve their sustainability.•We investigate the efficiency of a conceptual model of mobile-app-based business for SMEs.•The analysis suggests that SMEsneed a powerful mobile-app-based business network to succeed in the entrepreneurial business process. Small and Medium-Sized Enterprises (SMEs) are struggling to cope with the business uncertainty caused by the COVID-19 pandemic. This study examines how SMEs in developing economies have used mobile apps to improve their business efficiency during the pandemic. We aim to recognize effective measures and actions taken by SMEs that have turned to mobile-app-based business to improve their sustainability during the crisis. The study bridges a literature gap by extending the Theory of Consumption Values and the Theory of Planned Behavior to SMEs that incorporate mobile-app-based business. Data was collected from 343 SMEs from three Industrial Development Corporations (IDCs) in India. Using the covariance-based structural equation modeling method, we investigated the efficiency of a conceptual model of mobile-app-based business for SMEs. The results revealed that consumer choice behavior, perceived behavior control, subjective behavior control and attitude towards the mobile app all influence SMEs’ decision-making and business strategy. As such, SMEsneed a powerful mobile-app-based business network to succeed in the entrepreneurial business process. Using instrumental variable analysis, we discovered that increased mobile app usage significantly improves SMEs’ long-term efficiency. The analysis provides several theoretical and managerial ramifications.