Service innovations in modern economies are driven by the need to gain competitive advantage, technology advancements, market demand and organizational innovation. Uniquely, the need for social development presents opportunities for service innovations in developing nations, particularly in the delivery of social services. The thriving mobile industry in the continent provides new possibilities for development practitioners to design services that might fill gaps in social service delivery for poor communities. The challenge facing development-oriented innovations is sustainability. Sustainability is attained through continuous value generation for users and service owner(s). Proposals to developers of these innovations have therefore focused on business model application and evaluations to ascertain their ability to generate value. The complexity however of service innovation in the modern mobile industry requires a unique perspective of service design and evaluation. This paper introduces the STOF model, a business model framework for mobile service innovations in modern economies to an existing developmentoriented service innovation in Uganda. The framework uses the model’s four domains (Service, Technology, Organization and Finance) and their relational Critical Success Factors (CSF), to define and evaluate the innovation. These CSF were defined from web publications on the innovation. The evaluation discovered that some of the CSF, due to poor design and strategic decisions, where poorly defined and formulated, which in turn caused an imbalance in the overall business model and therefore value generation.