This app is Fabulous! As an Optician I am so happy to have the Slab and Vertex calculator! Quickly validating my assessment of the fundamental issues pertaining to the Rx is extremely useful. The determination of how best to fine tune the eyewear to the patients real world of viewing is essential. Grateful to have it.

Handy all-in-one calculator for all eyecare professionals. Looking forward to the addition of a finished lens thickness calculator in a future update.

Obliquely crossed cylinder app is helpful for soft toric fits and easy to use. Formulas are included for those who are interested. Seller responds quickly to emails and is open to all suggestions. Will add a diopter to mm and reverse function for conversion of K readings in diopters to mm for RGP fitting on the next update

I had been waiting for an application like this since I switched from my Treo which had these calculators. The interface is easy to use and provide great data for any eye care professional. Some of the calculators may be more academic than clinical, but they work well. I emailed the programmer and asked him to add an oblique cross cyl calculator for refracting over toric contact lenses and he was more happy to start working on adding it in one of the next updates. I am thrilled to have this resource and someone who is so willing to take suggestions to make it even better.

Unable to enter axis on vertex formula.

The cross cylinder calculations now work again with system 3.0. Great!!