# Eterna vs Chain

The clearest difference is in-app purchases: Eterna at none against Chain's 3. Eterna also leads on iOS requirement (12.0 vs 15.0). Chain's advantage is update cadence (weekly vs every 3 months). On price, ads and device support there is nothing between them.

Both are free to download. Chain sells 3 in-app purchases, starting at $2.99 per month. Eterna asks for nothing beyond the download.

Eterna ships an update every 3 months, Chain weekly. The most recent releases landed on November 4, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | Eterna | Chain |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | — | 90.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Weekly** |
| Monetization | — | Freemium |
| Size | 42 MB | 21 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Eterna Inc.](https://appshunter.io/developer/1500225556) | [Muhammed Talha POLAT](https://appshunter.io/developer/1731811922) |

## What reviewers say

### Eterna

[App page](https://appshunter.io/ios/app/eterna/id6477453458)

**Features:** macOS Compatibility

**In-app purchases:** none


### Chain

[App page](https://appshunter.io/ios/app/chain-habit-tracker-and-streak/id6478146486)

This app helps you build positive habits and break negative ones through a visual tracking system. Set goals, monitor daily progress, and receive reminders to stay on track. Customize your experience with themes and gain insights into your long-term progress.

**Highlights:** Build unbreakable habit chains, Daily progress tracking with calendar view, Set and achieve personal goals, Routine loop for habit acquisition, Customizable reminders, Motivational quotes and insights, User-friendly interface with themes

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Chain Pro Access - Monthly | $2.99 | per month |
| Chain Pro Access - Annual | $12.99 | per year |
| Chain Pro Access Lifetime | $24.99 | one-time |


## Frequently asked questions

### Is Eterna free?

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

### Is Chain free?

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

### Do Eterna or Chain have ads?

Neither Eterna nor Chain shows ads.

### Which is updated more often, Eterna or Chain?

Eterna ships an update every 3 months, and Chain weekly. Most recently, Eterna was updated on November 4, 2026 and Chain on October 30, 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.*