# Change Chain vs Cognitive Diary

The clearest difference is in-app purchases: Change Chain at none against Cognitive Diary's 2. Change Chain also leads on update cadence (every 3 days vs fortnightly) and iOS requirement (13.0 vs 16.4). On price, ads and device support there is nothing between them.

Both are free to download. Cognitive Diary sells 2 in-app purchases, starting at $0.99 per month. Change Chain asks for nothing beyond the download.

Change Chain ships an update every 3 days, Cognitive Diary fortnightly. The most recent releases landed on October 3, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | Change Chain | Cognitive Diary |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 3 days** | Fortnightly |
| Size | 21 MB | 60 MB |
| Requires iOS | **13.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 17+ |
| Developer | [Livanda - Internetkliniken AB](https://appshunter.io/developer/1607972909) | [Vitalii Kovalov](https://appshunter.io/developer/1864691271) |

## What reviewers say

### Change Chain

[App page](https://appshunter.io/ios/app/change-chain/id1644319974)

**Features:** macOS Compatibility

**In-app purchases:** none


### Cognitive Diary

[App page](https://appshunter.io/ios/app/cognitive-diary/id6757118591)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PRO | $0.99 | per month |
| PRO | $9.99 | per year |


## Frequently asked questions

### Is Change Chain free?

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

### Is Cognitive Diary free?

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

### Do Change Chain or Cognitive Diary have ads?

Neither Change Chain nor Cognitive Diary shows ads.

### Which is updated more often, Change Chain or Cognitive Diary?

Change Chain ships an update every 3 days, and Cognitive Diary fortnightly. Most recently, Change Chain was updated on October 3, 2026 and Cognitive Diary on September 28, 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.*