# ゼロカーボン・チャレンジ vs X

The clearest difference is update cadence: X at weekly against ゼロカーボン・チャレンジ's monthly. 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.

ゼロカーボン・チャレンジ ships an update monthly, X weekly. The most recent releases landed on November 4, 2026 and November 6, 2026 respectively.

## The numbers

| Metric | ゼロカーボン・チャレンジ | X |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/id6475059135/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Monthly | **Weekly** |
| Size | 29 MB | 29 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 12+ | 12+ |
| Developer | [JAPAN ZERO CARBON SMART CITY FOUNDATION, GENERAL INC. ASSOCIATION - AXFG5J98TW](https://appshunter.io/developer/1723265776) | [SHINYA KUDO](https://appshunter.io/developer/6815071944) |

## What reviewers say

### ゼロカーボン・チャレンジ

[App page](https://appshunter.io/ios/app/id6475059135)

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

**In-app purchases:** none


### X

[App page](https://appshunter.io/ios/app/x-year-diary/id6815105945)

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

**In-app purchases:** none


## Frequently asked questions

### Is ゼロカーボン・チャレンジ free?

ゼロカーボン・チャレンジ is free to download, with no in-app purchases.

### Is X free?

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

### Do ゼロカーボン・チャレンジ or X have ads?

Neither ゼロカーボン・チャレンジ nor X shows ads.

### Which is updated more often, ゼロカーボン・チャレンジ or X?

ゼロカーボン・チャレンジ ships an update monthly, and X weekly. Most recently, ゼロカーボン・チャレンジ was updated on November 4, 2026 and X on November 6, 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.*