# Tetra Twist vs Block Harmonics

The clearest difference is update cadence: Block Harmonics at every 9 days against Tetra Twist's every 3 months. Tetra Twist's advantage is iOS requirement (12.0 vs 15.1). On price, ads, in-app purchases and device support there is nothing between them.

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

Tetra Twist ships an update every 3 months, Block Harmonics every 9 days. Both last shipped on October 30, 2026.

## The numbers

| Metric | Tetra Twist | Block Harmonics |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | Yes | Yes |
| Update frequency | Every 3 months | **Every 9 days** |
| Size | 219 MB | 31 MB |
| Requires iOS | **12.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Tuan Tran Anh](https://appshunter.io/developer/1577568146) | [Ikuya Terasaka](https://appshunter.io/developer/1163471139) |

## What reviewers say

### Tetra Twist

[App page](https://appshunter.io/ios/app/tetra-twist/id6451078946)

**Features:** macOS Compatibility

**In-app purchases:** none


### Block Harmonics

[App page](https://appshunter.io/ios/app/block-harmonics/id6752220613)

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

**In-app purchases:** none


## Frequently asked questions

### Is Tetra Twist free?

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

### Is Block Harmonics free?

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

### Do Tetra Twist or Block Harmonics have ads?

Both Tetra Twist and Block Harmonics show ads.

### Which is updated more often, Tetra Twist or Block Harmonics?

Tetra Twist ships an update every 3 months, and Block Harmonics every 9 days. Most recently, Tetra Twist was updated on October 30, 2026 and Block Harmonics on October 30, 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.*