Digital Public Infrastructure and Sectoral Transformation in India: Evidence from Multi-Sector Startup Innovation

India's Digital Public Infrastructure (DPI) has become the main force which drives complete economic changes in different sectors of the economy. India established its digital infrastructure which operates at large scale through its public digital systems that include Aadhaar, Unified Payments Interface (UPI), Account Aggregator Framework, Open Network for Digital Commerce (ONDC), Ayushman Bharat Digital Mission, and Goods and Services Tax Network. The research shows how Digital Public Infrastructure (DPI) has driven changes in various sectors through startup development of new technologies from 2016 to 2025. The research study uses a comparative longitudinal research design which depends entirely on secondary data that comes from the Reserve Bank of India, National Payments Corporation of India, DPIIT, Startup India database, ONDC reports, ABDM dashboards and industry publications. The evaluation involves two parts which assess startup development in six sectors, namely FinTech, HealthTech, Agri Tech, Retail Tech, MSME services, and EdTech. The evaluation process requires a comparison between sector growth patterns and Digital Public Infrastructure (DPI) adoption benchmarks, which include digital transaction volumes and merchant onboarding and health ID registrations and consent-based financial data sharing. Using compound annual growth rate (CAGR) analysis, trend comparisons, and sectoral mapping, the study assesses the strength of association between DPI expansion and startup ecosystem development. Preliminary evidence indicates that sectors directly integrated with DPI layers demonstrate accelerated growth relative to indirectly integrated sectors. FinTech and Retail Tech startups exhibit strong expansion aligned with UPI adoption and ONDC network growth, while HealthTech innovation correlates with the rollout of ABDM digital health IDs. The Account Aggregator ecosystem and digital GST-based formalisation have further enabled data-driven lending, embedded finance models, and MSME digital inclusion. The findings suggest that DPI functions not merely as a digitisation tool but as a structural enabler of new business models, including platform-based commerce, API-driven services, consent-based credit architecture, and interoperable public–private innovation systems. The study contributes to entrepreneurship and innovation literature by conceptualising DPI as a form of public digital capital that reshapes sectoral value chains, reduces market entry barriers, and democratises access to digital markets. DPI establishes network effects which enable different industries to innovate through its use as digital infrastructure. Policy implications show that organizations need to maintain their open-access digital systems which support interoperability to achieve inclusive growth and drive innovative progress. The public digital architecture models of India demonstrate that digital public infrastructure serves as a fundamental driver for entrepreneurial growth across multiple sectors.