# Door（ドゥーア） vs THETA（シィータ）

The clearest difference is update cadence: Door（ドゥーア） at every 6 months against THETA（シィータ）'s every 42 months. THETA（シィータ）'s advantage is iOS requirement (8.0 vs 13.0). 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.

Door（ドゥーア） ships an update every 6 months, THETA（シィータ） every 42 months. The most recent releases landed on November 11, 2026 and November 7, 2026 respectively.

## The numbers

| Metric | Door（ドゥーア） | THETA（シィータ） |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 6 months** | Every 42 months |
| Size | 3 MB | 3 MB |
| Requires iOS | 13.0 | **8.0** |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Naoya Takahashi](https://appshunter.io/developer/1301211980) | [Naoya Takahashi](https://appshunter.io/developer/1301211980) |

## What reviewers say

### Door（ドゥーア）

[App page](https://appshunter.io/ios/app/door/id1361006449)

**Features:** macOS Compatibility

**In-app purchases:** none


### THETA（シィータ）

[App page](https://appshunter.io/ios/app/theta/id1517988653)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Door（ドゥーア） free?

Door（ドゥーア） is free to download, with no in-app purchases.

### Is THETA（シィータ） free?

THETA（シィータ） is free to download, with no in-app purchases.

### Do Door（ドゥーア） or THETA（シィータ） have ads?

Neither Door（ドゥーア） nor THETA（シィータ） shows ads.

### Which is updated more often, Door（ドゥーア） or THETA（シィータ）?

Door（ドゥーア） ships an update every 6 months, and THETA（シィータ） every 42 months. Most recently, Door（ドゥーア） was updated on November 11, 2026 and THETA（シィータ） on November 7, 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.*