# Two Links Double Pendulum vs ChattyAI

The clearest difference is in-app purchases: Two Links Double Pendulum at none against ChattyAI's 3. ChattyAI's advantage is update cadence (every 3 weeks vs every 47 months) and iOS requirement (16.2 vs 18.2). On price, ads and device support there is nothing between them.

Both are free to download. ChattyAI sells 3 in-app purchases, starting at $0.99 per 7 days. Two Links Double Pendulum asks for nothing beyond the download.

Two Links Double Pendulum ships an update every 47 months, ChattyAI every 3 weeks. Both last shipped on November 3, 2026.

## The numbers

| Metric | Two Links Double Pendulum | ChattyAI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (2 ratings)](https://appshunter.io/ios/app/chattyai-chatbot-and-keyboardai/id6446040611/reviews)** |
| Number of ratings | — | **2** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 47 months | **Every 3 weeks** |
| Monetization | — | Free with in-app purchases |
| Size | 281 MB | 5 MB |
| Requires iOS | 18.2 | **16.2** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 17+ |
| Developer | [Eliott Radcliffe](https://appshunter.io/developer/1477487767) | [Worathiti Manosroi](https://appshunter.io/developer/964821519) |

## What reviewers say

### 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


### ChattyAI

[App page](https://appshunter.io/ios/app/chattyai-chatbot-and-keyboardai/id6446040611)

Engage with an advanced AI chatbot featuring diverse personas and a convenient keyboard extension. Enjoy private, ad-free conversations stored locally without needing an account.

**Highlights:** Advanced language model interaction, Variety of unique AI personas, Keyboard extension for in-app use, Local conversation storage for privacy, No account creation required, Ad-free and distraction-free experience

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly | $0.99 | per 7 days |
| Monthly | $2.99 | per month |
| Yearly | $17.99 | per year |


## Frequently asked questions

### Is Two Links Double Pendulum free?

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

### Is ChattyAI free?

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

### Do Two Links Double Pendulum or ChattyAI have ads?

Neither Two Links Double Pendulum nor ChattyAI shows ads.

### Which is updated more often, Two Links Double Pendulum or ChattyAI?

Two Links Double Pendulum ships an update every 47 months, and ChattyAI every 3 weeks. Most recently, Two Links Double Pendulum was updated on November 3, 2026 and ChattyAI on November 3, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*