# F.A.S.T baby vs Two Links Double Pendulum

The clearest difference is iOS requirement: F.A.S.T baby at 15.6 against Two Links Double Pendulum's 18.2. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

F.A.S.T baby ships an update every 55 months, Two Links Double Pendulum every 47 months. The most recent releases landed on October 24, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | F.A.S.T baby | Two Links Double Pendulum |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.3 (11 ratings)](https://appshunter.io/ios/app/fast-baby/id1217030601/reviews)** | — |
| Number of ratings | **11** | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 55 months | **Every 47 months** |
| Monetization | Free | — |
| Size | 1 MB | 281 MB |
| Requires iOS | **15.6** | 18.2 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Philippe Zay](https://appshunter.io/developer/1200498230) | [Eliott Radcliffe](https://appshunter.io/developer/1477487767) |

## What reviewers say

### F.A.S.T baby

[App page](https://appshunter.io/ios/app/fast-baby/id1217030601)

This app offers a calming visual experience for babies and very young children with colorful, moving spiral patterns. Tapping the screen generates new spirals, or they change automatically after a brief pause, providing a simple and engaging display.

**Highlights:** Tap to generate new spirals, Automatic spiral changes, Simple full-screen interface, Designed for young children, Colorful moving patterns

**Features:** macOS Compatibility

**In-app purchases:** none


### Two Links Double Pendulum

[App page](https://appshunter.io/ios/app/two-links-double-pendulum/id1625794656)

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

**In-app purchases:** none


## Frequently asked questions

### Is F.A.S.T baby free?

F.A.S.T baby is free to download, with no in-app purchases.

### Is Two Links Double Pendulum free?

Two Links Double Pendulum is free to download, with no in-app purchases.

### Do F.A.S.T baby or Two Links Double Pendulum have ads?

Neither F.A.S.T baby nor Two Links Double Pendulum shows ads.

### Which is updated more often, F.A.S.T baby or Two Links Double Pendulum?

F.A.S.T baby ships an update every 55 months, and Two Links Double Pendulum every 47 months. Most recently, F.A.S.T baby was updated on October 24, 2026 and Two Links Double Pendulum on October 31, 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.*