Helpful

Helpful in figuring out the PD, but it has some limitations. One fixable limitation is that it would be easier to use if it allowed one to rotate the picture as will as zoom and center. Surprisingly difficult to take a perfectly level photo of oneself! Another fixable minor item is the app setting says credit card is 86.5mm but googling this says 85.6mm - easily fixable by a custom width. The more challenging limitations are: (1) for measurements relative to the credit card width to be accurate, the distance form the camera to the credit card needs to be exactly the distance form the camera to the pupils. The more I tried to figure out how to tilt the head to compensate, the less confident I was it was accurate. The front facing camera is at the top of the iPhone so the distance to the pupils is closer than the credit card. Trying the credit card on the forehead just above the pupils may be a bit more accurate, though the pupils are always a bit more inset that the credit card will be. If I spend half a day I could probably use my physics background to do some calculations so that if the camera is level with the eyes the math is built into the app for the credit card just below the nose…that might be a good improvement for the next version. (2) Very, very difficult to try to do a distant stare so the distance PD is measured and not a close PD focused not the camera just a foot away. For the next version might be good to incorporate some physics calculations into the math so that you do focus at 1 foot on the camera and the app give both the close PD and then calculates a distant PD. Those 2 changes would certainly deserve a 5 star

Joe____B about Pupil Meter