This study explores whether digitalisation of unorganised retail (UR) businesses in emerging markets have a positive socio-economic impact on the lives of the subsistence consumer–merchants who perform the dual role of being, not only consumers providing for themselves and their families, but also the managers of micro-UR businesses. We develop a framework for sustainable business model innovation at the base of the pyramid by undertaking content analysis of 65 newspaper articles (interviews with senior executives and founders of digital app-based platforms, expert analysis) as well as social media and YouTube testimonials of UR business users of these platforms in Vietnam, Indonesia, Malaysia and the Philippines. Using the Gioian coding structure of open and second order comparative coding, we develop a framework for sustainable business model innovation from the base of the pyramid perspective. The framework captures how digitalisation enables the UR businesses to circumvent resource shortages, consolidate procurement and inventory management and diversify product and service offerings, which leads to significant economic and social transformation for both the micro enterprises and their owners. Our framework contributes to the emergent literature on sustainable business model innovation and inclusive innovation in resource-constrained contexts. We conclude that sustainable business model innovations enable socio-economic transformations similar to those experienced by UR businesses in emerging Asian markets. Such developments can create local level pathways for local tropical countries seeking to achieve UN social development goals.