# 51大师兄 vs 兰树办公OA

The clearest difference is in-app purchases: 兰树办公OA at none against 51大师兄's 10. 兰树办公OA also leads on ads (none vs shown). 51大师兄's advantage is iOS requirement (13.0 vs 15). On price, update cadence and device support there is nothing between them.

Both are free to download. 51大师兄 sells 10 one-off in-app purchases. 兰树办公OA asks for nothing beyond the download.

51大师兄 ships an update every 2 weeks, 兰树办公OA every 3 weeks. The most recent releases landed on October 8, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | 51大师兄 | 兰树办公OA |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Every 2 weeks** | Every 3 weeks |
| Size | 339 MB | 97 MB |
| Requires iOS | **13.0** | 15 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Big Brother Shanghai Cloud Data Service Co., Ltd](https://appshunter.io/developer/1533046678) | [浙江兰树化妆品有限公司](https://appshunter.io/developer/1588006508) |

## What reviewers say

### 51大师兄

[App page](https://appshunter.io/ios/app/51-ai/id1533046676)

**Features:** macOS Compatibility

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1个月普通大师兄会员 | $7.99 | one-time |
| 3个月普通大师兄会员 | $19.99 | one-time |
| 3个月普通大师兄会员 | $20.99 | one-time |
| 6个月金牌大师兄会员 | $45.99 | one-time |
| 1年普通大师兄会员 | $59.99 | one-time |
| 1年金牌大师兄会员 | $74.99 | one-time |
| 1年普通大师兄会员 | $79.99 | one-time |
| 1年金牌大师兄会员 | $79.99 | one-time |
| 1年钻石大师兄会员 | $79.99 | one-time |
| 1年钻石大师兄会员 | $89.99 | one-time |


### 兰树办公OA

[App page](https://appshunter.io/ios/app/oa/id1593158623)

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

**In-app purchases:** none


## Frequently asked questions

### Is 51大师兄 free?

51大师兄 is free to download, with in-app purchases available.

### Is 兰树办公OA free?

兰树办公OA is free to download, with no in-app purchases.

### Do 51大师兄 or 兰树办公OA have ads?

51大师兄 shows ads; 兰树办公OA does not.

### Which is updated more often, 51大师兄 or 兰树办公OA?

51大师兄 ships an update every 2 weeks, and 兰树办公OA every 3 weeks. Most recently, 51大师兄 was updated on October 8, 2026 and 兰树办公OA on October 24, 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.*