Gizmos & Gadgets: Do-it-Yourself Eye Glass Prescription App Comes to Smartphones

The age of the mobile phone doctor is upon us and it covers everything from self-monitoring your heart, to diagnosing a number of diseases, and now determining your eyeglass prescription.

EyeNetra has created a device called the Netra-G.With it you can do your own eye test to determine if you are farsighted, nearsighted, have astigmatism, suffer from age-related eye blurring or other common problem that can be corrected by lenses. Netra-G provides a technology that is equivalent to what today’s optometrists do with autorefractors that cost from $5,000 to $45,000 U.S.

Netra-G measures the OD, OS, SPH, CYL, Axis, and distance between the eyes. If you are unfamiliar with any of these terms here is quick reference:


  • OD, it stands for right eye or oculus dexter.
  • OS stands for left eye or oculus sinister.
  • SPH is short for Sphere which measures lens power in units called diopters. A minus diopter value means you are nearsighted. A plus value means you are farsighted.
  • CYL and Axis measure lens requirements to correct astigmatism.




Netra-G looks like a cheap binocular that you attach to your smartphone. When combined with the accompanying app it gives consumers the means to do an instant eye exam which they can then bring to an eye doctor to get confirmation. Technology like this is bound to be disruptive to the $75 billion a year industry.




Netra-G is one product in a growing list of technologies that empower smartphone users to do self diagnosis. Others include Cellscope Oto (TM) (inner ear imaging), AliveCor (electrocardiogram), Quanttus (heart rate and blood pressure), Scanadu Scout (temperature, heart rate and blood oxygen levels) and iBGTStar (blood glucose).

Len Rosen lives in Toronto, Ontario, Canada. He is a researcher and writer who has a fascination with science and technology. He is married with a daughter who works in radio, and a miniature red poodle who is his daily companion on walks of discovery. More...