# Sample Size Calculator vs FocusFlow

The clearest difference is in-app purchases: Sample Size Calculator at none against FocusFlow's 2. Sample Size Calculator also leads on update cadence (every 6 days vs monthly) and device support (3 vs 1). On price and ads there is nothing between them.

Both are free to download. FocusFlow sells 2 in-app purchases, starting at $5.99 per month. Sample Size Calculator asks for nothing beyond the download.

Sample Size Calculator ships an update every 6 days, FocusFlow monthly. The most recent releases landed on September 19, 2026 and September 11, 2026 respectively.

## The numbers

| Metric | Sample Size Calculator | FocusFlow |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 6 days** | Monthly |
| Size | 24 MB | 45 MB |
| Requires iOS | **9.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Relief Applications](https://appshunter.io/developer/1110805584) | [Giress Kenne tsasse](https://appshunter.io/developer/1849295885) |

## What reviewers say

### Sample Size Calculator

[App page](https://appshunter.io/ios/app/sample-size-calculator-light/id1436831899)

**Features:** macOS Compatibility

**In-app purchases:** none


### FocusFlow

[App page](https://appshunter.io/ios/app/focusflow-screen-time/id6754619731)

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| FocusFlow Premium - Monthly | $5.99 | per month |
| FocusFlow Premium - Annual | $49.99 | per year |


## Frequently asked questions

### Is Sample Size Calculator free?

Sample Size Calculator is free to download, with no in-app purchases.

### Is FocusFlow free?

FocusFlow is free to download, with in-app purchases available.

### Do Sample Size Calculator or FocusFlow have ads?

Neither Sample Size Calculator nor FocusFlow shows ads.

### Which is updated more often, Sample Size Calculator or FocusFlow?

Sample Size Calculator ships an update every 6 days, and FocusFlow monthly. Most recently, Sample Size Calculator was updated on September 19, 2026 and FocusFlow on September 11, 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.*