Teleoptometry and smartphone-associated visual habits across the lifespan

The spread of smartphones has seen an extraordinary growth in recent years, a condition that asks for detailed studies to identify visual habits and visual health associated with their use. In the present study, we measured viewing distance and character size across different age groups while participants read a simple text message. We also assessed the precision of a specific teleoptometry application in estimating smartphone usage distance. Our results showed that both reading distance and character size differed across age with non-presbyopes using closer distances and smaller character sizes as compared to presbyopes. We also found that a teleoptometry smartphone application exploiting the built-in front camera reliably assessed device usage distance with an average error lying below the value usually considered critical in clinical practice. In summary, our data reveal that visual habits in the use of smartphones can substantially vary across age, and suggest interesting future scenarios for teleoptometry to reliably predict visual health status.