# True Solar Time （真太陽時） vs I Ching Calendar

The clearest difference is ads: I Ching Calendar at none against True Solar Time （真太陽時）'s shown. True Solar Time （真太陽時）'s advantage is update cadence (every 5 days vs every 5 weeks) and iOS requirement (13.0 vs 17.6). On price, in-app purchases and device support there is nothing between them.

Both are free to download. True Solar Time （真太陽時） sells 1 one-off in-app purchase and I Ching Calendar sells 3 in-app purchases, starting at $1.99 per 7 days. Whichever you choose, the download price is not the number that matters.

True Solar Time （真太陽時） ships an update every 5 days, I Ching Calendar every 5 weeks. The most recent releases landed on October 28, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | True Solar Time （真太陽時） | I Ching Calendar |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/i-ching-calendar/id6784172213/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | **Every 5 days** | Every 5 weeks |
| Monetization | — | Free with in-app purchases |
| Size | 24 MB | 13 MB |
| Requires iOS | **13.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [Tsz Fung Shing](https://appshunter.io/developer/1877613702) | [帮兰 吴](https://appshunter.io/developer/1729036017) |

## What reviewers say

### True Solar Time （真太陽時）

[App page](https://appshunter.io/ios/app/true-solar-time/id6759240543)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 購買移除廣告 | $4.99 | one-time |


### I Ching Calendar

[App page](https://appshunter.io/ios/app/i-ching-calendar/id6784172213)

This comprehensive folk custom app offers a perpetual calendar, auspicious date selection, numerology analysis, and health management tools. It integrates traditional Zhouyi culture with modern planning features for daily life and significant events.

**Highlights:** Perpetual calendar with Gregorian & lunar lookup, Auspicious date selector for events, Traditional numerology analysis (Eight-character, marriage matching), Eastern & Western divination (hexagrams, Tarot, horoscopes), Seasonal health manager with period tracker, Name numerology suite for baby naming and renaming

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Professional | $1.99 | per 7 days |
| Professional | $2.99 | per month |
| Professional | $19.99 | per year |


## Frequently asked questions

### Is True Solar Time （真太陽時） free?

True Solar Time （真太陽時） is free to download, with in-app purchases available.

### Is I Ching Calendar free?

I Ching Calendar is free to download, with in-app purchases available.

### Do True Solar Time （真太陽時） or I Ching Calendar have ads?

True Solar Time （真太陽時） shows ads; I Ching Calendar does not.

### Which is updated more often, True Solar Time （真太陽時） or I Ching Calendar?

True Solar Time （真太陽時） ships an update every 5 days, and I Ching Calendar every 5 weeks. Most recently, True Solar Time （真太陽時） was updated on October 28, 2026 and I Ching Calendar on October 31, 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.*