Determine resultant lens over existing lens combined with over refraction. Makes contact lens fitting more accurate. Useful in refining high powered eyeglass prescriptions using over refraction. Quick and easy to use application determines resulting contact lens prescription or spectacle prescription using lens currently worn and over refraction data. Exact results or round to one quarter diopter.

What’s New

Version 1.11

update to swift code

Ratings and Reviews

4.0 out of 5
1 Rating

1 Rating

Eyeyeyeyeye ,

Axis error

Past version
This app has a drum system and is easy to use, I have found some glitches. Firstly, the axis drums have an erroneous axis of 169 which should be 160. Secondly, a negative axis appears. This is not a big problem in that by subtracting that number from 180 gives the correct axis. For example, if lens worn is +2.50-1.75x167 and the Over Refraction is Plano-0.25x30, the result is +2.50-1.75x-9. -9 is equivalent to x171.
Axis problem is fixed. Recommend increasing range of spheres to + / - 20D. Or having an optional window to type in the needed power.
Typing in an axis may save time spinning the drum.

benichols ,

Axis incorrect

I would gladly change my rating if this bug is fixed but I can’t find anywhere to contact the developer. It calculates axis wrong. If you enter +2.00-1.75x175 for glasses and over refract 0.00-0.50x90 the result it gives is +1.51-1.26x83 (it won’t round this result either), which is incorrect.
I cannot currently recommend purchasing this app until the error is corrected.


Alta Vista LLC
19.6 MB

Requires iOS 8.1 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating
Rated 4+
© Copy Right 2015 Alta Vista LLC All rights reserved.


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