Transfer of technology is rapidly evolving from traditional, top-down, face-to-face methods where experts directly instruct farmers toward integrated, digitally enabled, multi-channel advisory systems. Digital technologies including mobile applications, SMS advisories, IoT sensors, AI-driven analytics, and decision-support systems (DSS) offer unprecedented opportunities to enhance outreach, deliver personalized recommendations, strengthen farmer decision-making, and improve resource-use efficiency. These tools can facilitate two-way communication, integrating local knowledge and feedback into extension services, while also supporting market linkages, climate risk management, and sustainability goals. Evidence indicates that mobile and SMS-based advisories are highly inclusive and scalable, whereas IoT, AI, and DSS represent advanced precision technologies with adoption challenges due to costs, digital literacy, connectivity, and institutional capacity. While digital extension can increase productivity, incomes, and resilience, it also risks reinforcing existing inequalities and creating dependencies if accessibility, local relevance, trust, and human facilitation are insufficiently addressed. Key barriers include digital literacy gaps, content localization, gender and socio-economic inequities, data governance, and institutional limitations. Successful digital agriculture requires blended extension models, participatory content design, capacity-building, inclusive service and financing mechanisms, and robust policy frameworks. This review synthesizes recent empirical and market evidence on digital agriculture adoption, impacts on knowledge, productivity, and market access, and identifies research gaps and best practices for inclusive, sustainable, and scalable digital extension services.