Society 5.0, proposed as part of the 5th Science and Technology Basic Plan by Japan's National Institute of Advanced Industrial Science and Technology, is a human-centered society where cyberspace and physical space are integrated, to resolve social challenges and promote economic growth. In Society 5.0, medicine will undergo extensive digital transformation (DX), and digital health technology is expected to expand markedly, becoming part of routine clinical practice. Prompt diagnosis of dry eye disease (DED) and uninterrupted monitoring of such patients with healthcare barriers is currently an unmet need. DX of DED evaluation and management can boost the current quality of DED care. Software as Medical Devices (SaMDs), i.e., software programs developed through evidence-based research to provide diagnostic, therapeutic, and preventive services, and particularly medical devices based on smartphone applications (apps), have attracted attention. We have striven to actualize the DX of ophthalmic care and evaluation, denoted by our ongoing development of SaMDs to assist DED diagnosis. To illustrate healthcare using the Internet of Medical Things, we here present the research and development process of our smartphone app-based SaMD for DED diagnosis assistance.