# VDrop vs Transformer Calculator.

The clearest difference is in-app purchases: VDrop at none against Transformer Calculator.'s 1. VDrop also leads on ads (none vs shown) and rating (5.0 vs 4.8). Transformer Calculator.'s advantage is update cadence (every 4 months vs every 13 months) and ratings volume (47 vs 3). On price and device support there is nothing between them.

Both are free to download. Transformer Calculator. sells 1 one-off in-app purchase. VDrop asks for nothing beyond the download.

VDrop holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Transformer Calculator. has 47 ratings behind it against 3, so its average is the more settled of the two.

VDrop ships an update every 13 months, Transformer Calculator. every 4 months. The most recent releases landed on June 1, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | VDrop | Transformer Calculator. |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (3 ratings)](https://appshunter.io/ios/app/vdrop/id1461666751/reviews)** | [4.8 (47 ratings)](https://appshunter.io/ios/app/transformer-calculator/id1506155081/reviews) |
| Number of ratings | 3 | **47** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 13 months | **Every 4 months** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 13 MB | 41 MB |
| Requires iOS | **10.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Nebulous LLC](https://appshunter.io/developer/1448637140) | [V PUGAZHENTHI](https://appshunter.io/developer/491898049) |

## What reviewers say

### VDrop

[App page](https://appshunter.io/ios/app/vdrop/id1461666751)

This utility calculates voltage drop for electrical systems up to 600V. It provides detailed calculation outputs to help users verify results and build confidence in their electrical work. Custom voltage inputs are supported.

**Highlights:** Voltage drop calculations, Supports up to 600V, Custom voltage input, Detailed calculation outputs, User confidence building

**Features:** macOS Compatibility

**In-app purchases:** none


### Transformer Calculator.

[App page](https://appshunter.io/ios/app/transformer-calculator/id1506155081)

This app simplifies transformer calculations for engineers and students. It accurately computes primary and secondary currents, turns ratios, and secondary voltages based on user inputs for transformer ratings and winding turns.

**Highlights:** Primary and secondary current calculations, Turns ratio determination, Transformer type identification, Secondary voltage calculation, Supports 1Φ and 3Φ phases, User-friendly interface

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Go Pro | $3.99 | one-time |


## Frequently asked questions

### Is VDrop free?

VDrop is free to download, with no in-app purchases.

### Is Transformer Calculator. free?

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

### Which has better reviews, VDrop or Transformer Calculator.?

VDrop is rated higher. VDrop averages 5.0 out of 5 from 3 ratings, while Transformer Calculator. averages 4.8 from 47 ratings.

### Do VDrop or Transformer Calculator. have ads?

Transformer Calculator. shows ads; VDrop does not.

### Which is updated more often, VDrop or Transformer Calculator.?

VDrop ships an update every 13 months, and Transformer Calculator. every 4 months. Most recently, VDrop was updated on June 1, 2026 and Transformer Calculator. on September 18, 2026.

---

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