# LSTclock vs MahjongScore

The clearest difference is in-app purchases: LSTclock at none against MahjongScore's 1. LSTclock also leads on ads (none vs shown). MahjongScore's advantage is update cadence (every 5 days vs every 2 months) and iOS requirement (15.1 vs 18.0). On price and device support there is nothing between them.

Both are free to download. MahjongScore sells 1 in-app purchase, starting at $0.99 per month. LSTclock asks for nothing beyond the download.

LSTclock ships an update every 2 months, MahjongScore every 5 days. The most recent releases landed on October 24, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | LSTclock | MahjongScore |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.8 (10 ratings)](https://appshunter.io/ios/app/lstclock-sidereal-time-clock/id1510148631/reviews)** | — |
| Number of ratings | **10** | — |
| Positive reviews | 54.5% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 2 months | **Every 5 days** |
| Monetization | Free | — |
| Size | 22 MB | 42 MB |
| Requires iOS | 18.0 | **15.1** |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Tsuyoshi Sawada](https://appshunter.io/developer/1510148630) | [TAISEI OKADA](https://appshunter.io/developer/1824433238) |

## What reviewers say

### LSTclock

[App page](https://appshunter.io/ios/app/lstclock-sidereal-time-clock/id1510148631)

This utility app displays local sidereal time for registered locations on iOS, iPadOS, and watchOS. It can also calculate sidereal time and Julian Date for any date and time, and sync locations between devices.

**Highlights:** Local sidereal time display, Julian Date calculation, Supports multiple registered locations, Location sync between iPhone and Apple Watch, Date and time specific calculations

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases:** none


### MahjongScore

[App page](https://appshunter.io/ios/app/mahjongscoreauto-calculation/id6792716929)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| プレミアム（月額） | $0.99 | per month |


## Frequently asked questions

### Is LSTclock free?

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

### Is MahjongScore free?

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

### Do LSTclock or MahjongScore have ads?

MahjongScore shows ads; LSTclock does not.

### Which is updated more often, LSTclock or MahjongScore?

LSTclock ships an update every 2 months, and MahjongScore every 5 days. Most recently, LSTclock was updated on October 24, 2026 and MahjongScore on October 8, 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.*