# TWO【公式】 vs Aerien

TWO【公式】 and Aerien are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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 38 months. The most recent releases landed on September 30, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | TWO【公式】 | Aerien |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 38 months | Every 38 months |
| Size | 34 MB | 19 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 12+ | 12+ |
| Developer | [TAIKI KOIZUMI](https://appshunter.io/developer/1569870683) | [KODAI SEITO](https://appshunter.io/developer/1630907620) |

## What reviewers say

### TWO【公式】

[App page](https://appshunter.io/ios/app/two/id1569870681)

**In-app purchases:** none


### Aerien

[App page](https://appshunter.io/ios/app/aerien/id1630907618)

**In-app purchases:** none


## Frequently asked questions

### Is TWO【公式】 free?

TWO【公式】 is free to download, with no in-app purchases.

### Is Aerien free?

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

### Do TWO【公式】 or Aerien have ads?

Neither TWO【公式】 nor Aerien shows ads.

### Which is updated more often, TWO【公式】 or Aerien?

TWO【公式】 ships an update every 38 months, and Aerien every 38 months. Most recently, TWO【公式】 was updated on September 30, 2026 and Aerien on September 28, 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.*