# Calculate Standard Deviation vs σT

The clearest difference is in-app purchases: σT at none against Calculate Standard Deviation's 1. σT also leads on ads (none vs shown) and update cadence (fortnightly vs every 7 months). Calculate Standard Deviation's advantage is iOS requirement (15.0 vs 26.2). On price and device support there is nothing between them.

Both are free to download. Calculate Standard Deviation sells 1 one-off in-app purchase. σT asks for nothing beyond the download.

Calculate Standard Deviation ships an update every 7 months, σT fortnightly. The most recent releases landed on October 3, 2026 and October 16, 2026 respectively.

## The numbers

| Metric | Calculate Standard Deviation | σT |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (62 ratings)](https://appshunter.io/ios/app/calculate-standard-deviation/id1591420646/reviews)** | — |
| Number of ratings | **62** | — |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 7 months | **Fortnightly** |
| Monetization | Free with in-app purchases | — |
| Size | 39 MB | 6 MB |
| Requires iOS | **15.0** | 26.2 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Asad Ahsan](https://appshunter.io/developer/1326954499) | [YARON AMIR BENJAMIN DR. GOLDSTEIN](https://appshunter.io/developer/1850455880) |

## What reviewers say

### Calculate Standard Deviation

[App page](https://appshunter.io/ios/app/calculate-standard-deviation/id1591420646)

This app calculates standard deviation, variance, and other statistical measures for a given set of values. It simplifies complex statistical formulas with a user-friendly interface and accurate results.

**Highlights:** Calculate Standard Deviation, Calculate Variance, Calculate Mean, Calculate Coefficient of Variance, Calculate Standard Error of Mean, User-friendly interface, Accurate statistical results

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Standard Deviation Premium | $4.99 | one-time |


### σT

[App page](https://appshunter.io/ios/app/t/id6756549182)

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

**In-app purchases:** none


## Frequently asked questions

### Is Calculate Standard Deviation free?

Calculate Standard Deviation is free to download, with in-app purchases available.

### Is σT free?

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

### Do Calculate Standard Deviation or σT have ads?

Calculate Standard Deviation shows ads; σT does not.

### Which is updated more often, Calculate Standard Deviation or σT?

Calculate Standard Deviation ships an update every 7 months, and σT fortnightly. Most recently, Calculate Standard Deviation was updated on October 3, 2026 and σT on October 16, 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.*