# R1+R2 Zs Ze Calculator — user reviews

> 10 indexed App Store user reviews of R1+R2 Zs Ze Calculator by Pro Certs Software Ltd.

- Source: https://appshunter.io/ios/app/r1-plus-r2-zs-ze-calculator/id572416784/reviews
- App overview in markdown: https://appshunter.io/ios/app/r1-plus-r2-zs-ze-calculator/id572416784.md

## Most critical reviews (10 lowest-rated)

### 1/5 — Update

*2018-01-09*

Unfortunately this version does not work on the iPhone

**Developer response:** App now updated for iOS 11 & new UI redesign.

### 1/5 — Basic math

*2016-10-27*

If you need this app to do the calculations this app does, you need to find a new job.
Basic math that most electricians could do in their head.

### 1/5 — Oo

*2012-12-10*

Not a good app. As a calculator to add Ze to [R1+R2] to obtain Zs it's ok. But to use the calculation Zs - [R1+R2] as this app does to obtain Ze is wrong. Ze is either obtained by enquiry from the DNO, or measured with the system isolated, and with all bonding disconnected. Ze is the External EFLI.

**Developer response:** App now updated for iOS 11 & new UI redesign.

### 2/5 — Not good

*2018-08-24*

I agree with Basic Math if you need this app you definitely need a knew job

### 2/5 — Hhmm

*2013-05-31*

As mentioned by "22w" the ze calculation is wrong. This should be measured!!

**Developer response:** App now updated for iOS 11 & new UI redesign.

### 5/5 — Great app

*2021-05-19*

Simple helpful app to make calculations faultless

### 5/5 — Very good app.

*2012-11-22*

Great app, very useful and handy.

### 5/5 — Ze + Zs (R1 + R2) calculator

*2012-11-10, version 1.0*

Great little app. Very handy.

### 5/5 — Zs Ze app

*2012-11-05*

Great app, very useful. 5 stars!

### 5/5 — Very good

*2012-10-31*

Great app and very useful.

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-24.*