# Southwire® Voltage Drop Calc vs SimplyAuth

The clearest difference is in-app purchases: Southwire® Voltage Drop Calc at none against SimplyAuth's 2. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. SimplyAuth sells 2 in-app purchases, starting at $0.99 per month. Southwire® Voltage Drop Calc asks for nothing beyond the download.

Southwire® Voltage Drop Calc ships an update every 2 months, SimplyAuth every 3 months. The most recent releases landed on November 1, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Southwire® Voltage Drop Calc | SimplyAuth |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (1.5K ratings)](https://appshunter.io/ios/app/southwire-voltage-drop-calc/id440338420/reviews)** | — |
| Number of ratings | **1.5K** | — |
| Positive reviews | 49.1% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 3 months |
| Monetization | Free | — |
| Size | 10 MB | 57 MB |
| Requires iOS | **15.0** | 15.1 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Southwire Company](https://appshunter.io/developer/440338423) | [SimplyAuth LLC](https://appshunter.io/developer/1889629727) |

## What reviewers say

### Southwire® Voltage Drop Calc

[App page](https://appshunter.io/ios/app/southwire-voltage-drop-calc/id440338420)

Calculate the appropriate wire size for electrical circuits. This tool helps determine wire size based on voltage drop and current carrying capacity, ensuring compliance with NEC ampacity limits.

**Highlights:** Determine wire size for voltage drop, Calculate voltage drop for conductor runs, Limit wire size by voltage drop, Limit wire size by NEC ampacity, Supports AWG and KCMIL sizes

**Features:** macOS Compatibility

**In-app purchases:** none

**What reviewers like**

- 🚀 Quick and useful
- 🚀 Great Quick Reference
- 👍 A must have app for electricians
- 👍 Love These
- 👍 Electrical Engineer

**What reviewers complain about**

- 🐛 Motor starting Voltage drop
- 🐛 Useless!
- 🐛 Won't work
- 🐛 How to use
- 🐛 Confused

**Reported bugs**

- Useless!
- Won't work
- How to use
- Confused
- Bad app

**Requested features**

- Motor starting Voltage drop calculation
- Metric wire size options


### SimplyAuth

[App page](https://appshunter.io/ios/app/simplyauth/id6761439612)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Personal | $0.99 | per month |
| Personal | $7.99 | per year |


## Frequently asked questions

### Is Southwire® Voltage Drop Calc free?

Southwire® Voltage Drop Calc is free to download, with no in-app purchases.

### Is SimplyAuth free?

SimplyAuth is free to download, with in-app purchases available.

### Do Southwire® Voltage Drop Calc or SimplyAuth have ads?

Neither Southwire® Voltage Drop Calc nor SimplyAuth shows ads.

### Which is updated more often, Southwire® Voltage Drop Calc or SimplyAuth?

Southwire® Voltage Drop Calc ships an update every 2 months, and SimplyAuth every 3 months. Most recently, Southwire® Voltage Drop Calc was updated on November 1, 2026 and SimplyAuth on October 25, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*