# Messier Journal vs MessierMate

The clearest difference is price: MessierMate at Free against Messier Journal's $0.99. MessierMate also leads on update cadence (monthly vs every 3 months) and iOS requirement (16.4 vs 18.0). On rating, review sentiment, ratings volume and ads there is nothing between them.

MessierMate is free to download; Messier Journal costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 5.0 for Messier Journal against 5.0 for MessierMate. Both are backed by a comparable volume of ratings — 3 and 3 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

Messier Journal ships an update every 3 months, MessierMate monthly. Both last shipped on October 28, 2026.

## The numbers

| Metric | Messier Journal | MessierMate |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | [5.0 (3 ratings)](https://appshunter.io/ios/app/messier-journal/id6753959873/reviews) | [5.0 (3 ratings)](https://appshunter.io/ios/app/messiermate-night-sky-tracker/id6782169332/reviews) |
| Number of ratings | 3 | 3 |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 months | **Monthly** |
| Monetization | Paid | **Free** |
| Size | 158 MB | 70 MB |
| Requires iOS | 18.0 | **16.4** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Damon Degner](https://appshunter.io/developer/1845946345) | [CosmicFlow Labs LLC](https://appshunter.io/developer/1882544353) |

## What reviewers say

### Messier Journal

[App page](https://appshunter.io/ios/app/messier-journal/id6753959873)

This app helps Northern Hemisphere astronomers and astrophotographers discover, locate, and journal all 110 Messier objects. It provides detailed information, star maps, and tools to record observations and upload photos.

**Highlights:** Learn about 110 Messier objects, Locate objects with star maps, Filter objects by constellation and type, Record observation details, Upload astrophotography, Track spotted object statistics, Generate object collages

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

**In-app purchases:** none


### MessierMate

[App page](https://appshunter.io/ios/app/messiermate-night-sky-tracker/id6782169332)

This free astronomy app helps deep-sky observers track celestial objects. It shows what's visible in your sky tonight, sorted by urgency, and allows you to plan future observing sessions and log your observations. It features a dark theme and red night mode for preserving night vision.

**Highlights:** Track 110 Messier objects, Real-time altitude and azimuth, Urgency-based object sorting, Monthly planning calendar, Session logging with notes and photos, Offline functionality, Red Night mode

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

**In-app purchases:** none


## Frequently asked questions

### Is Messier Journal free?

Messier Journal costs $0.99, with no in-app purchases.

### Is MessierMate free?

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

### Which has better reviews, Messier Journal or MessierMate?

Messier Journal and MessierMate are both rated 5.0 out of 5 on the App Store, from 3 and 3 ratings respectively.

### Do Messier Journal or MessierMate have ads?

Neither Messier Journal nor MessierMate shows ads.

### Which is updated more often, Messier Journal or MessierMate?

Messier Journal ships an update every 3 months, and MessierMate monthly. Most recently, Messier Journal was updated on October 28, 2026 and MessierMate on October 28, 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.*