# 愛する我が子への手紙 vs 睡眠ドッグ

The clearest difference is ads: 睡眠ドッグ at none against 愛する我が子への手紙's shown. 睡眠ドッグ also leads on update cadence (every 2 weeks vs every 4 months). 愛する我が子への手紙's advantage is device support (3 vs 1) and iOS requirement (13.0 vs 17.0). On price 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.

愛する我が子への手紙 ships an update every 4 months, 睡眠ドッグ every 2 weeks. The most recent releases landed on October 5, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | 愛する我が子への手紙 | 睡眠ドッグ |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 4 months | **Every 2 weeks** |
| Size | 63 MB | 9 MB |
| Requires iOS | **13.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 9+ |
| Developer | [Anderson Oki](https://appshunter.io/developer/1525688631) | [Hayato Kitaoka](https://appshunter.io/developer/1634161426) |

## What reviewers say

### 愛する我が子への手紙

[App page](https://appshunter.io/ios/app/id1596713005)

**Features:** macOS Compatibility

**In-app purchases:** none


### 睡眠ドッグ

[App page](https://appshunter.io/ios/app/id6475922311)

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

**In-app purchases:** none


## Frequently asked questions

### Is 愛する我が子への手紙 free?

愛する我が子への手紙 is free to download, with no in-app purchases.

### Is 睡眠ドッグ free?

睡眠ドッグ is free to download, with no in-app purchases.

### Do 愛する我が子への手紙 or 睡眠ドッグ have ads?

愛する我が子への手紙 shows ads; 睡眠ドッグ does not.

### Which is updated more often, 愛する我が子への手紙 or 睡眠ドッグ?

愛する我が子への手紙 ships an update every 4 months, and 睡眠ドッグ every 2 weeks. Most recently, 愛する我が子への手紙 was updated on October 5, 2026 and 睡眠ドッグ on October 4, 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.*