# RF Engineer's Calc vs PhosphorHertz

The clearest difference is price: RF Engineer's Calc at Free against PhosphorHertz's $0.99. RF Engineer's Calc also leads on iOS requirement (16.1 vs 26.2). PhosphorHertz's advantage is update cadence (every 4 months vs every 10 months). On ads, in-app purchases and device support there is nothing between them.

RF Engineer's Calc is free to download; PhosphorHertz costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

RF Engineer's Calc ships an update every 10 months, PhosphorHertz every 4 months. The most recent releases landed on October 6, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | RF Engineer's Calc | PhosphorHertz |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 10 months | **Every 4 months** |
| Size | 43 MB | 5 MB |
| Requires iOS | **16.1** | 26.2 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [GRAHAM JOHN SMITH](https://appshunter.io/developer/1668396908) | [Stuart Woolley](https://appshunter.io/developer/315697638) |

## What reviewers say

### RF Engineer's Calc

[App page](https://appshunter.io/ios/app/rf-engineers-calc/id1668396906)

**Features:** macOS Compatibility

**In-app purchases:** none


### PhosphorHertz

[App page](https://appshunter.io/ios/app/phosphorhertz/id6759729656)

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

**In-app purchases:** none


## Frequently asked questions

### Is RF Engineer's Calc free?

RF Engineer's Calc is free to download, with no in-app purchases.

### Is PhosphorHertz free?

PhosphorHertz costs $0.99, with no in-app purchases.

### Do RF Engineer's Calc or PhosphorHertz have ads?

Neither RF Engineer's Calc nor PhosphorHertz shows ads.

### Which is updated more often, RF Engineer's Calc or PhosphorHertz?

RF Engineer's Calc ships an update every 10 months, and PhosphorHertz every 4 months. Most recently, RF Engineer's Calc was updated on October 6, 2026 and PhosphorHertz on October 14, 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.*