# 理旦 vs 知己

The clearest difference is in-app purchases: 知己 at none against 理旦's 2. 理旦's advantage is iOS requirement (17 vs 26.0). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. 理旦 sells 2 in-app purchases, starting at $2.99 per month. 知己 asks for nothing beyond the download.

理旦 ships an update every 6 days, 知己 every 3 days. The most recent releases landed on November 6, 2026 and November 10, 2026 respectively.

## The numbers

| Metric | 理旦 | 知己 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 6 days | **Every 3 days** |
| Size | 109 MB | 10 MB |
| Requires iOS | **17** | 26.0 |
| Devices | iPhone | iPhone |
| Age rating | 17+ | 12+ |
| Developer | [元子旦科技(成都)有限公司](https://appshunter.io/developer/1879746735) | [伟烈 熊](https://appshunter.io/developer/6792607821) |

## What reviewers say

### 理旦

[App page](https://appshunter.io/ios/app/id6791475343)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 理旦月度会员 | $2.99 | per month |
| 理旦加油包 | $2.99 | one-time |


### 知己

[App page](https://appshunter.io/ios/app/ai/id6816163811)

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

**In-app purchases:** none


## Frequently asked questions

### Is 理旦 free?

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

### Is 知己 free?

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

### Do 理旦 or 知己 have ads?

Neither 理旦 nor 知己 shows ads.

### Which is updated more often, 理旦 or 知己?

理旦 ships an update every 6 days, and 知己 every 3 days. Most recently, 理旦 was updated on November 6, 2026 and 知己 on November 10, 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.*