# 發球 Serve vs U

The clearest difference is iOS requirement: 發球 Serve at 17.0 against U's 26.4. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Both ship on a similar rhythm, roughly every 2 weeks. The most recent releases landed on November 5, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | 發球 Serve | U |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 weeks | Every 2 weeks |
| Size | 37 MB | 10 MB |
| Requires iOS | **17.0** | 26.4 |
| Devices | iPhone | **iPhone, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [發球股份有限公司](https://appshunter.io/developer/1873056869) | [Yao YungTai](https://appshunter.io/developer/6805562795) |

## What reviewers say

### 發球 Serve

[App page](https://appshunter.io/ios/app/serve/id6758462897)

**Features:** macOS Compatibility

**In-app purchases:** none


### U

[App page](https://appshunter.io/ios/app/u-dive/id6805562793)

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is 發球 Serve free?

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

### Is U free?

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

### Do 發球 Serve or U have ads?

Neither 發球 Serve nor U shows ads.

### Which is updated more often, 發球 Serve or U?

發球 Serve ships an update every 2 weeks, and U every 2 weeks. Most recently, 發球 Serve was updated on November 5, 2026 and U on October 29, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*