# Cautionary vs 序日

The clearest difference is price: 序日 at Free against Cautionary's $0.99. Cautionary's advantage is in-app purchases (none vs 1) and iOS requirement (16.4 vs 18.0). On update cadence, ads and device support there is nothing between them.

序日 is free to download; Cautionary costs $0.99 up front. 序日 sells 1 one-off in-app purchase. Cautionary asks for nothing beyond the download.

Cautionary ships an update every 3 days, 序日 daily. The most recent releases landed on October 25, 2026 and October 26, 2026 respectively.

## The numbers

| Metric | Cautionary | 序日 |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/id6811274043/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 days | **Daily** |
| Size | 11 MB | 21 MB |
| Requires iOS | **16.4** | 18.0 |
| Devices | **iPhone, iPad, Mac** | iPhone, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [辉章 何](https://appshunter.io/developer/1687027088) | [琦 张](https://appshunter.io/developer/6811089301) |

## What reviewers say

### Cautionary

[App page](https://appshunter.io/ios/app/cautionary/id6451156147)

**Features:** Vision Pro support

**In-app purchases:** none


### 序日

[App page](https://appshunter.io/ios/app/id6811274043)

**Features:** Apple Watch app

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 序日 Pro · One-time Purchase | $1.99 | one-time |


## Frequently asked questions

### Is Cautionary free?

Cautionary costs $0.99, with no in-app purchases.

### Is 序日 free?

序日 is free to download, with in-app purchases available.

### Do Cautionary or 序日 have ads?

Neither Cautionary nor 序日 shows ads.

### Which is updated more often, Cautionary or 序日?

Cautionary ships an update every 3 days, and 序日 daily. Most recently, Cautionary was updated on October 25, 2026 and 序日 on October 26, 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.*