# 密九邮箱 vs Cerberus

The clearest difference is in-app purchases: 密九邮箱 at none against Cerberus's 3. 密九邮箱 also leads on iOS requirement (12.0 vs 16.4). Cerberus's advantage is update cadence (every 9 days vs every 5 months). On price, ads and device support there is nothing between them.

Both are free to download. Cerberus sells 3 in-app purchases, starting at $2.99 per month. 密九邮箱 asks for nothing beyond the download.

密九邮箱 ships an update every 5 months, Cerberus every 9 days. The most recent releases landed on November 7, 2026 and November 6, 2026 respectively.

## The numbers

| Metric | 密九邮箱 | Cerberus |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 9 days** |
| Size | 43 MB | 61 MB |
| Requires iOS | **12.0** | 16.4 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [ShenZhen AoLian Information Security Technology Co.,Ltd.](https://appshunter.io/developer/1580917948) | [Shahen Grigoryan](https://appshunter.io/developer/1839815556) |

## What reviewers say

### 密九邮箱

[App page](https://appshunter.io/ios/app/id1591371248)

**Features:** macOS Compatibility

**In-app purchases:** none


### Cerberus

[App page](https://appshunter.io/ios/app/cerberus-private-secure-chat/id6811835565)

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Cerberus Pro Monthly | $2.99 | per month |
| Cerberus Pro Yearly | $14.99 | per year |
| AirPact: Private Secure Chat | $29.99 | one-time |


## Frequently asked questions

### Is 密九邮箱 free?

密九邮箱 is free to download, with no in-app purchases.

### Is Cerberus free?

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

### Do 密九邮箱 or Cerberus have ads?

Neither 密九邮箱 nor Cerberus shows ads.

### Which is updated more often, 密九邮箱 or Cerberus?

密九邮箱 ships an update every 5 months, and Cerberus every 9 days. Most recently, 密九邮箱 was updated on November 7, 2026 and Cerberus on November 6, 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.*