The present invention is directed to a digital aroma system that provides a scented air on demand to various devices in various forms and user held devices including: remote controls, video game controllers and mobile computing devices. Dry fragrance infused substrates are contained in fragrance cartridges that are removably mounted in a cassette that is connected to a manifold that has airway passages that are connected to fans or pumps that are controlled by a computer processor. In response to a fragrance control signal or a fragrance trigger, the processor can selectively direct scented air having a specified fragrance to a system user.