# Astrolabe Clock vs APT Darkness Clock

The clearest difference is rating: APT Darkness Clock at 5.0 against Astrolabe Clock's 4.7. APT Darkness Clock also leads on update cadence (every 11 days vs every 4 weeks) and review sentiment (100% vs 91%). Astrolabe Clock's advantage is ratings volume (48 vs 4). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

APT Darkness Clock holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Astrolabe Clock has 48 ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 91% of Astrolabe Clock's written reviews are positive against 100% of APT Darkness Clock's.

Astrolabe Clock ships an update every 4 weeks, APT Darkness Clock every 11 days. The most recent releases landed on September 15, 2026 and September 8, 2026 respectively.

## The numbers

| Metric | Astrolabe Clock | APT Darkness Clock |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.7 (48 ratings)](https://appshunter.io/ios/app/astrolabe-clock/id421777015/reviews) | **[5.0 (4 ratings)](https://appshunter.io/ios/app/apt-darkness-clock/id1351332907/reviews)** |
| Number of ratings | **48** | 4 |
| Positive reviews | 90.9% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 weeks | **Every 11 days** |
| Monetization | Free | Free |
| Size | 3 MB | 1 MB |
| Requires iOS | 15.6 | **10.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Michael Smith](https://appshunter.io/developer/415384088) | [Ivaylo Stoynov](https://appshunter.io/developer/1351332906) |

## What reviewers say

### Astrolabe Clock

[App page](https://appshunter.io/ios/app/astrolabe-clock/id421777015)

This app offers a modern interpretation of an ancient astronomical instrument, providing a real-time view of the sky. It displays the time of day, day of the year, and the positions of celestial bodies like the Sun, Moon, planets, and stars. Users can also track sunrise/sunset times, moon phases, and celestial transits.

**Highlights:** Real-time sky view, Time of day and day of year display, Sun, Moon, planet, and star locations, Sunrise and sunset times, Moon phase tracking, Celestial transit times, Eclipse occurrence indicator

**Features:** macOS Compatibility

**In-app purchases:** none


### APT Darkness Clock

[App page](https://appshunter.io/ios/app/apt-darkness-clock/id1351332907)

This app calculates the optimal times for deep sky astrophotography and observation based on your location and night sky conditions. It determines the duration and start/end times of ideal darkness, excluding twilight and moonlight.

**Highlights:** Calculates Deep Sky Darkness Time (DSD Time), Determines start and end times for DSD Time, Calculates DSD Time duration, Supports current location, Allows storing up to three observing sites, Free and ad-free

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Astrolabe Clock free?

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

### Is APT Darkness Clock free?

APT Darkness Clock is free to download, with no in-app purchases.

### Which has better reviews, Astrolabe Clock or APT Darkness Clock?

APT Darkness Clock is rated higher. Astrolabe Clock averages 4.7 out of 5 from 48 ratings, while APT Darkness Clock averages 5.0 from 4 ratings.

### Do Astrolabe Clock or APT Darkness Clock have ads?

Neither Astrolabe Clock nor APT Darkness Clock shows ads.

### Which is updated more often, Astrolabe Clock or APT Darkness Clock?

Astrolabe Clock ships an update every 4 weeks, and APT Darkness Clock every 11 days. Most recently, Astrolabe Clock was updated on September 15, 2026 and APT Darkness Clock on September 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.*