# Biological clock vs Chess master tutorial Quiz

The clearest difference is price: Biological clock at Free against Chess master tutorial Quiz's $5.99. Biological clock also leads on iOS requirement (12.1 vs 15.1). Chess master tutorial Quiz's advantage is ads (none vs shown) and update cadence (every 3 months vs every 13 months). On in-app purchases and device support there is nothing between them.

Biological clock is free to download; Chess master tutorial Quiz costs $5.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Biological clock ships an update every 13 months, Chess master tutorial Quiz every 3 months. The most recent releases landed on October 26, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Biological clock | Chess master tutorial Quiz |
| --- | --- | --- |
| Price | **Free** | $5.99 |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 13 months | **Every 3 months** |
| Size | 13 MB | 56 MB |
| Requires iOS | **12.1** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 12+ |
| Developer | [HAREPPO](https://appshunter.io/developer/604325074) | [Blupry](https://appshunter.io/developer/1737667517) |

## What reviewers say

### Biological clock

[App page](https://appshunter.io/ios/app/biological-clock-everywhere/id1099546322)

**Features:** Vision Pro support

**In-app purchases:** none


### Chess master tutorial Quiz

[App page](https://appshunter.io/ios/app/chess-master-tutorial-quiz/id1570426648)

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

**In-app purchases:** none


## Frequently asked questions

### Is Biological clock free?

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

### Is Chess master tutorial Quiz free?

Chess master tutorial Quiz costs $5.99, with no in-app purchases.

### Do Biological clock or Chess master tutorial Quiz have ads?

Biological clock shows ads; Chess master tutorial Quiz does not.

### Which is updated more often, Biological clock or Chess master tutorial Quiz?

Biological clock ships an update every 13 months, and Chess master tutorial Quiz every 3 months. Most recently, Biological clock was updated on October 26, 2026 and Chess master tutorial Quiz on October 25, 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.*