Messier Journal vs SkyChecker
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Messier Journal
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.
- 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
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For astrophotographers and visual astronomers in the Northern Hemisphere, who are collecting Messier objects. This app will help you learn about, locate, and journal all 110 objects from the Messier Catalog. It is a great way to keep an organized record of finding these celestial wonders. FEATURES LEARN: All 110 Messier objects are included with brief descriptions and photos. LOCATE: Detailed star maps and right-ascension/declination coordinates included with each object. FILTER: Narrow your search by constellation, difficulty, object type, peak month, & season. EXPECTATIONS: What you can expect to see using binoculars, and small, medium, & large size telescopes. PHOTO ALBUM: Upload photos from your - sketches, smartphone eyepiece views, astrophoto rig, or smart telescope. FAVORITES: Mark your favorite Messier objects. DETAILS: Record date, time, location, equipment used, magnification, and any other pertinent notes. STAT TRACKER: Keeps track of spotted object statistics by constellation, difficulty, object type, & season. COLLAGE GENERATOR: Generate a collage of your captured objects. BACKUP: Export/import options to transfer data between iOS devices. SECURE: No sign in, no cloud, no tracking. You control your data & it remains on your device.
SkyChecker
Identify celestial objects visible from your location with real-time data. Track planets, galaxies, meteor showers, and the ISS. Includes weather integration and planning tools for optimal stargazing.
- Celestial object tracking
- Weather integration for viewing conditions
- Observation planning tools
- Automatic GPS location detection
- Retro terminal-style interface
- ISS pass tracking
- Meteor shower alerts
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Discover whaDiscover what's visible in the night sky tonight — right from your backyard. SkyChecker uses NASA's Jet Propulsion Laboratory data to show you exactly which celestial objects are visible from your location. No guesswork, no complicated star charts — just a simple list of what you can see and when. WHAT YOU CAN TRACK • The Moon with current phase and illumination percentage • All planets from Mercury to Neptune • Deep sky objects: Andromeda Galaxy, Orion Nebula, Pleiades, and more • International Space Station (ISS) passes • Meteor shower alerts with peak times and hourly rates WEATHER INTEGRATION • Live cloud cover and visibility conditions • Observation quality rating (1-5 stars) • Detailed weather breakdown: humidity, wind, cloud layers • Tips for optimal viewing based on current conditions PLANNING TOOLS • Equipment difficulty ratings (Naked Eye, Binoculars, Telescope) • Rise, set, and peak viewing times with compass directions • Date picker to plan future observing sessions • Share tonight's sky with friends and family POWERFUL FEATURES • Automatic GPS location detection • Manual coordinate entry for precise locations • Smart caching for fast app launch • Elegant retro terminal-style interface with ASCII art HOW IT WORKS SkyChecker connects to NASA's Horizons Ephemeris System — the same data source used by professional astronomers — to calculate precise positions for celestial objects based on your exact location and time zone. Weather data comes from Open-Meteo, providing real-time cloud cover, visibility, and atmospheric conditions to help you plan the perfect observing session. PERFECT FOR • Casual stargazers curious about tonight's sky • Amateur astronomers planning observation sessions • Educators teaching astronomy concepts • Anyone who's ever looked up and wondered "what's that?" PRIVACY FOCUSED Your location stays on your device. We don't track you, collect personal data, or show ads. The only external connections are to NASA's public astronomical database and Open-Meteo weather service. Clear skies!
Screenshots
Verdict
The clearest difference is price: SkyChecker at Free against Messier Journal's $0.99. SkyChecker also leads on update cadence (every 4 weeks vs every 3 months) and iOS requirement (16.0 vs 18.0). On rating, review sentiment, ratings volume and ads there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
SkyChecker 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 SkyChecker. Both are backed by a comparable volume of ratings — 3 and 2 respectively. Written reviews split almost evenly too, at 100% and 100% positive.
Messier Journal ships an update every 3 months, SkyChecker every 4 weeks. The most recent releases landed on October 28, 2026 and September 24, 2026 respectively.
| Parameter | Messier Journal | SkyChecker |
|---|---|---|
| Price | $0.99 | Free — better |
| Rating | 5.0 (3 ratings) | 5.0 (2 ratings) |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| Number of ratings | 3 — better | 2 |
| Update frequency | Every 3 months | Every 4 weeks — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Free — better |
| Devices | iPhone, iPad | iPhone, iPad |
| Requires iOS | 18.0 | 16.0 — better |
| Further details — not scored | ||
| Size | 158 MB | 3 MB |
| Age rating | 4+ | 4+ |
| Developer | Damon Degner | ANDREW DAVID CHAMBERLAIN |
Customer experience
Messier Journal
SkyChecker
In-app purchases
Messier Journal
No in-app purchases
SkyChecker
No in-app purchases







