# PsyPad vs Standard Deviation Calc

The clearest difference is in-app purchases: PsyPad at none against Standard Deviation Calc's 1. Standard Deviation Calc's advantage is device support (3 vs 1). On price, update cadence, ads and iOS requirement there is nothing between them.

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

PsyPad ships an update every 4 months, Standard Deviation Calc every 5 months. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | PsyPad | Standard Deviation Calc |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.8 (12 ratings)](https://appshunter.io/ios/app/standard-deviation-calc-sd/id1497525733/reviews)** |
| Number of ratings | — | **12** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 5 months |
| Monetization | — | Free with in-app purchases |
| Size | 4 MB | 2 MB |
| Requires iOS | **13.5** | 14.0 |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Andrew Turpin](https://appshunter.io/developer/735057969) | [Phan Nhat Đang](https://appshunter.io/developer/1437390098) |

## What reviewers say

### PsyPad

[App page](https://appshunter.io/ios/app/psypad/id735057966)

**Features:** macOS Compatibility

**In-app purchases:** none


### Standard Deviation Calc

[App page](https://appshunter.io/ios/app/standard-deviation-calc-sd/id1497525733)

Calculate standard deviation for sample or population data. Input numerical values to find standard deviation, count, sum, mean, variance, and more. Get quick statistical insights with this easy-to-use tool.

**Highlights:** Calculate standard deviation, Sample or population data, Compute mean and variance, Count numerical values, Sum of numbers, List of differences

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove ads | $1.99 | one-time |


## Frequently asked questions

### Is PsyPad free?

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

### Is Standard Deviation Calc free?

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

### Do PsyPad or Standard Deviation Calc have ads?

Neither PsyPad nor Standard Deviation Calc shows ads.

### Which is updated more often, PsyPad or Standard Deviation Calc?

PsyPad ships an update every 4 months, and Standard Deviation Calc every 5 months. Most recently, PsyPad was updated on November 1, 2026 and Standard Deviation Calc on November 3, 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.*