# e vs Three

The clearest difference is in-app purchases: e at none against Three's 1. On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Three sells 1 one-off in-app purchase. e asks for nothing beyond the download.

e ships an update every 2 days, Three every 4 days. The most recent releases landed on October 17, 2026 and October 19, 2026 respectively.

## The numbers

| Metric | e | Three |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/three-body-simulation/id6817179834/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 2 days** | Every 4 days |
| Monetization | — | Free with in-app purchases |
| Size | 29 MB | 6 MB |
| Requires iOS | **15.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Jiten Roy](https://appshunter.io/developer/1674372293) | [志强 曾](https://appshunter.io/developer/1800987336) |

## What reviewers say

### e

[App page](https://appshunter.io/ios/app/e-population/id6757603869)

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

**In-app purchases:** none


### Three

[App page](https://appshunter.io/ios/app/three-body-simulation/id6817179834)

Explore the fascinating beauty of gravity and celestial motion. Interact with three bodies, discover countless orbital paths, and experiment with your own gravity scenarios. Turn curiosity into understanding with this educational simulation.

**Highlights:** Explore 16 classic periodic solutions, Discover 10,059 3D periodic orbits, Experiment with custom gravity scenarios, Learn about the three-body problem, Offline exploration of orbits, Interactive celestial motion simulation

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Lifetime Unlock | $0.99 | one-time |


## Frequently asked questions

### Is e free?

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

### Is Three free?

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

### Do e or Three have ads?

Neither e nor Three shows ads.

### Which is updated more often, e or Three?

e ships an update every 2 days, and Three every 4 days. Most recently, e was updated on October 17, 2026 and Three on October 19, 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.*