The World Health Organization (WHO) aims to eliminate trachoma, the world's leading infectious cause of blindness. To determine if trachoma treatment is needed in an area, the WHO recommends eye examinations on a population-based sample of children by personnel certified in trachoma grading. The WHO's successful trachoma elimination campaign has created a situation in which some areas have too many to trachoma cases to declare elimination but too few trachoma cases to certify trachoma graders. Adopting smartphone-based trachoma telemedicine addresses this issue by allowing workers with little clinical experience to perform trachoma photo-surveys for remote trachoma diagnoses. However, the WHO's current data collection platform for trachoma surveys, Tropical Data, does not currently support ocular photography. We propose here to integrate smartphone photography with Tropical Data and add functionality that will transform it into a more user-friendly, open access suite of smartphone-based survey modules. This would enhance flexibility and facilitate broader health surveys that can be used to better target limited health resources. This first part of the study aims to develop and refine the hardware and software necessary to integrate smartphone conjunctival photography into the Tropical Data platform, and to assess the feasibility of the resulting product in remote community-based settings in Peru. First, modules for photography, visual acuity assessment, autorefraction, sample collection, and user-defined questionnaires will be added to the existing Tropical Data application. Second, the impact of varying smartphone models and/or ambient lighting will be assessed for each module. Third, the updated mobile application will be tested in a small number of villages to determine the feasibility of testing multiple modules per child. The second part of the study validates the components of the smartphone-based system when used in three different field locations in Peru (e.g., jungle, mountains, desert). We will examine the sensitivity and specificity of smartphone photography relative to certified human graders, smartphone visual acuity relative to standard ETDRS visual acuity, and autorefraction relative to human refraction, and hypothesize that these metrics will be superior to pre-defined minimally acceptable criteria. The UCSF Proctor Foundation and Cayetano University in Peru will collaborate to achieve these goals. We will work in close cooperation with the WHO and Tropical Data, who will be actively engaged in this research throughout development and testing. This research has great potential for wide dissemination and positive impact on health.