# Spin Meter vs 321GO發射力

The clearest difference is iOS requirement: Spin Meter at 15.1 against 321GO發射力's 17.0. 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.

Spin Meter ships an update every 4 days, 321GO發射力 weekly. The most recent releases landed on September 14, 2026 and September 22, 2026 respectively.

## The numbers

| Metric | Spin Meter | 321GO發射力 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 days** | Weekly |
| Size | 18 MB | 50 MB |
| Requires iOS | **15.1** | 17.0 |
| Devices | **iPhone, iPad, iPod, Apple Watch** | iPhone, iPad, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [YUAN KUEI HSUEH](https://appshunter.io/developer/1884811594) | [byRoss Technology Co. Ltd.](https://appshunter.io/developer/1369578029) |

## What reviewers say

### Spin Meter

[App page](https://appshunter.io/ios/app/spin-meter/id6761355145)

**Features:** macOS Compatibility, Apple Watch app

**In-app purchases:** none


### 321GO發射力

[App page](https://appshunter.io/ios/app/321go/id6764324786)

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

**In-app purchases:** none


## Frequently asked questions

### Is Spin Meter free?

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

### Is 321GO發射力 free?

321GO發射力 is free to download, with no in-app purchases.

### Do Spin Meter or 321GO發射力 have ads?

Neither Spin Meter nor 321GO發射力 shows ads.

### Which is updated more often, Spin Meter or 321GO發射力?

Spin Meter ships an update every 4 days, and 321GO發射力 weekly. Most recently, Spin Meter was updated on September 14, 2026 and 321GO發射力 on September 22, 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.*