# Human Heroes Einstein’s Clock vs Einstein's Relativity

The clearest difference is in-app purchases: Human Heroes Einstein’s Clock at none against Einstein's Relativity's 2. Human Heroes Einstein’s Clock also leads on update cadence (every 2 months vs every 24 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Einstein's Relativity sells 2 one-off in-app purchases. Human Heroes Einstein’s Clock asks for nothing beyond the download.

Human Heroes Einstein’s Clock ships an update every 2 months, Einstein's Relativity every 24 months. The most recent releases landed on July 29, 2026 and February 21, 2026 respectively.

## The numbers

| Metric | Human Heroes Einstein’s Clock | Einstein's Relativity |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (32 ratings)](https://appshunter.io/ios/app/human-heroes-einsteins-clock/id1463380511/reviews)** | — |
| Number of ratings | **32** | — |
| Positive reviews | 82.8% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 24 months |
| Monetization | Free | — |
| Size | 183 MB | 322 MB |
| Requires iOS | **12.1** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Human Heroes Ltd](https://appshunter.io/developer/1442853426) | [Human Heroes Ltd](https://appshunter.io/developer/1442853426) |

## What reviewers say

### Human Heroes Einstein’s Clock

[App page](https://appshunter.io/ios/app/human-heroes-einsteins-clock/id1463380511)

Learn to tell time with an interactive 3D Albert Einstein, voiced by Stephen Fry. This free app offers 8 levels of clock-reading challenges, with visual and verbal guidance to help children master time concepts. It's an engaging introduction to the Human Heroes educational series.

**Highlights:** Interactive 3D Albert Einstein character, Voiced by Stephen Fry, 8 levels of clock-reading practice, O'Clock, quarter, half, past, and to time concepts, On-screen visual and verbal guidance, Offline play

**Features:** macOS Compatibility

**In-app purchases:** none


### Einstein's Relativity

[App page](https://appshunter.io/ios/app/einsteins-relativity/id6468444718)

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| The Sensation of Seconds | $0.99 | one-time |
| The Cadence Of Clocks | $0.99 | one-time |


## Frequently asked questions

### Is Human Heroes Einstein’s Clock free?

Human Heroes Einstein’s Clock is free to download, with no in-app purchases.

### Is Einstein's Relativity free?

Einstein's Relativity is free to download, with in-app purchases available.

### Do Human Heroes Einstein’s Clock or Einstein's Relativity have ads?

Neither Human Heroes Einstein’s Clock nor Einstein's Relativity shows ads.

### Which is updated more often, Human Heroes Einstein’s Clock or Einstein's Relativity?

Human Heroes Einstein’s Clock ships an update every 2 months, and Einstein's Relativity every 24 months. Most recently, Human Heroes Einstein’s Clock was updated on July 29, 2026 and Einstein's Relativity on February 21, 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.*