# Gravity Zen vs Chemle

The clearest difference is price: Chemle at Free against Gravity Zen's $0.99. Chemle also leads on in-app purchases (none vs 2) and iOS requirement (13.0 vs 15.0). On update cadence, ads and device support there is nothing between them.

Chemle is free to download; Gravity Zen costs $0.99 up front. Gravity Zen sells 2 one-off in-app purchases. Chemle asks for nothing beyond the download.

Gravity Zen ships an update every 9 days, Chemle every 2 weeks. The most recent releases landed on October 17, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | Gravity Zen | Chemle |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[4.8 (68 ratings)](https://appshunter.io/ios/app/gravity-zen/id1602081846/reviews)** | — |
| Number of ratings | **68** | — |
| Positive reviews | 93.3% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 9 days** | Every 2 weeks |
| Monetization | Paid | — |
| Size | 13 MB | 65 MB |
| Requires iOS | 15.0 | **13.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Dominik Hauser](https://appshunter.io/developer/325836858) | [Jan Stepien](https://appshunter.io/developer/1644539739) |

## What reviewers say

### Gravity Zen

[App page](https://appshunter.io/ios/app/gravity-zen/id1602081846)

Observe small circles interacting with a central gravity field. Add numerous boxes to explore how they naturally settle into a stable arrangement. It's a simple yet captivating simulation.

**Highlights:** Gravity field simulation, Add multiple objects, Observe stable configurations, Interactive physics, Minimalist design

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Small Tip | $0.99 | one-time |
| Large tip | $2.99 | one-time |


### Chemle

[App page](https://appshunter.io/ios/app/chemle/id6446223004)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Gravity Zen free?

Gravity Zen costs $0.99, and also offers in-app purchases.

### Is Chemle free?

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

### Do Gravity Zen or Chemle have ads?

Neither Gravity Zen nor Chemle shows ads.

### Which is updated more often, Gravity Zen or Chemle?

Gravity Zen ships an update every 9 days, and Chemle every 2 weeks. Most recently, Gravity Zen was updated on October 17, 2026 and Chemle on October 4, 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.*