Solar air heaters of many types have been developed in India and their performance studied in detail. The application of these air heaters are limited to a few demonstration projects for food dehydration, and space heating. Some of these case studies are described in this paper. For a few cash crops, the potential of solar air heaters for the drying process has been assessed in detail. Space heating by solar air heaters and their use for natural ventilation has also been discussed and results of a theoretical study presented to make out a case for more intensive research in the fields of solar air heater applications in India.