# splotRF vs Smith Charts

The clearest difference is price: splotRF at Free against Smith Charts's $3.99. splotRF also leads on rating (5.0 vs 3.7) and update cadence (every 10 days vs every 3 weeks). Smith Charts's advantage is iOS requirement (15.0 vs 18.0). On ratings volume, ads, in-app purchases and device support there is nothing between them.

splotRF is free to download; Smith Charts costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

splotRF holds the better App Store score, 5.0 against 3.7. Both are backed by a comparable volume of ratings — 2 and 3 respectively.

splotRF ships an update every 10 days, Smith Charts every 3 weeks. The most recent releases landed on September 10, 2026 and September 21, 2026 respectively.

## The numbers

| Metric | splotRF | Smith Charts |
| --- | --- | --- |
| Price | **Free** | $3.99 |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/splotrf/id1599892560/reviews)** | [3.7 (3 ratings)](https://appshunter.io/ios/app/smith-charts/id1602503719/reviews) |
| Number of ratings | 2 | **3** |
| Positive reviews | — | 66.7% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 10 days** | Every 3 weeks |
| Monetization | **Free** | Paid |
| Size | 6 MB | 24 MB |
| Requires iOS | 18.0 | **15.0** |
| Devices | iPhone, iPad, Mac | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [DirectRF](https://appshunter.io/developer/1572692412) | [Edoardo Orzes](https://appshunter.io/developer/1665361246) |

## What reviewers say

### splotRF

[App page](https://appshunter.io/ios/app/splotrf/id1599892560)

Visualize and analyze touchstone S-parameter data with interactive plots. Supports multiple file overlays, stability calculations, and various matrix conversions. Export data in vector graphics formats.

**Highlights:** Plot .snp format S-parameter data, Stability circles and µ/µ' analysis, Overlay multiple trace data, View data as a table, S/Y/Z matrix conversion, Smith Chart, Polar, and Rectangular plots, Export to PDF

**In-app purchases:** none


### Smith Charts

[App page](https://appshunter.io/ios/app/smith-charts/id1602503719)

Design matching networks, analyze device parameters, and compute stability circles with this interactive tool. Supports S parameters, various components, and offers advanced engineering features for RF design. Available in dark mode and exportable to PDF.

**Highlights:** Interactive Smith chart with drag and zoom, Design matching networks with various components, Compute stability, equi gain, and noise circles, Import S parameters from Touchstone files, Export designs to PDF, image, or file, Dark mode support, Ruler for wavelength measurement

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

**In-app purchases:** none


## Frequently asked questions

### Is splotRF free?

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

### Is Smith Charts free?

Smith Charts costs $3.99, with no in-app purchases.

### Which has better reviews, splotRF or Smith Charts?

splotRF is rated higher. splotRF averages 5.0 out of 5 from 2 ratings, while Smith Charts averages 3.7 from 3 ratings.

### Do splotRF or Smith Charts have ads?

Neither splotRF nor Smith Charts shows ads.

### Which is updated more often, splotRF or Smith Charts?

splotRF ships an update every 10 days, and Smith Charts every 3 weeks. Most recently, splotRF was updated on September 10, 2026 and Smith Charts on September 21, 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.*