# SimpleSigma+ vs SD Toolkit

The clearest difference is price: SD Toolkit at Free against SimpleSigma+'s $3.99. SD Toolkit also leads on device support (3 vs 1) and iOS requirement (14.0 vs 17.1). SimpleSigma+'s advantage is update cadence (every 3 weeks vs every 27 months). On ads and in-app purchases there is nothing between them.

SD Toolkit is free to download; SimpleSigma+ costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

SimpleSigma+ ships an update every 3 weeks, SD Toolkit every 27 months. Both last shipped on November 3, 2026.

## The numbers

| Metric | SimpleSigma+ | SD Toolkit |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | — | **[5.0 (2 ratings)](https://appshunter.io/ios/app/sd-toolkit/id1618642110/reviews)** |
| Number of ratings | — | **2** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 27 months |
| Monetization | Paid | **Free** |
| Size | 1 MB | 45 MB |
| Requires iOS | 17.1 | **14.0** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [MUTSUAKI KIKUCHI](https://appshunter.io/developer/1874283283) | [Satcom Direct](https://appshunter.io/developer/447415249) |

## What reviewers say

### SimpleSigma+

[App page](https://appshunter.io/ios/app/simplesigma-plus/id1522991950)

This app simplifies numerical tabulation with three distinct spreadsheet types for various calculation needs. It offers quick data input, immediate recalculation, and convenient features like CSV import/export and tax settings.

**Highlights:** Three spreadsheet types (Simple, Duplex, Shopping), Quick data input and immediate recalculation, Swipeable keyboard for cell navigation, Customizable consumption tax settings, Save and reuse calculation data, CSV data import and export

**Features:** macOS Compatibility

**In-app purchases:** none


### SD Toolkit

[App page](https://appshunter.io/ios/app/sd-toolkit/id1618642110)

Troubleshoot aviation satcom terminals via serial connection. This tool helps diagnose and resolve issues with satellite communication equipment used in aircraft.

**Highlights:** Troubleshoot satcom terminals, Serial connection support, Aviation specific, Diagnose communication issues

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

**In-app purchases:** none


## Frequently asked questions

### Is SimpleSigma+ free?

SimpleSigma+ costs $3.99, with no in-app purchases.

### Is SD Toolkit free?

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

### Do SimpleSigma+ or SD Toolkit have ads?

Neither SimpleSigma+ nor SD Toolkit shows ads.

### Which is updated more often, SimpleSigma+ or SD Toolkit?

SimpleSigma+ ships an update every 3 weeks, and SD Toolkit every 27 months. Most recently, SimpleSigma+ was updated on November 3, 2026 and SD Toolkit on November 3, 2026.

---

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