Comparison

Cosmic Deepsky vs Messier Journal

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Cosmic Deepsky

Explore the universe with a virtual telescope. Discover galaxies, star clusters, and nebulae with stunning real images and detailed information. A pocket guide to the cosmos.

Highlights
  • Virtual telescope functionality
  • Detailed information on 4000+ galaxies
  • Real astro-photographs of celestial objects
  • Hand-measured and oriented images
  • Exploration of deep sky objects
  • Information on star clusters and nebulae
Features
Read full description

Welcome to Cosmic Deepsky, where the marvels of the universe come alive through the lens of your device – your very own magic telescope. We live on a planet cruising through space, surrounded by the vast expanse of the cosmos. The canvas of our existence extends far beyond the confines of our planet, stretching into the depths of the celestial sphere above and below. By day, our atmosphere dances with the brilliance of sunlight, casting a cerulean glow upon the world. Yet, as night descends, a grand spectacle unfolds. Against the backdrop of darkness, myriad suns dot the heavens, weaving intricate constellations that have captivated humanity for millennia. Here, amidst the twinkling stars, lies the gateway to the deep sky – a realm where gas clouds and cosmic debris coalesce, painting celestial masterpieces with the strokes of light and gravity. Among these wonders, stars congregate in clusters, while others journey across the galactic plane in majestic arcs. Supernovae remnants and planetary systems adorn the spiral arms of our Milky Way galaxy, a cosmic tapestry of stellar life. Yet, the deep sky knows no bounds, extending far beyond our galactic borders to distant neighbors like the Magellanic Clouds and the majestic Andromeda galaxy. With Cosmic Deepsky, we invite you to peer into the depths of the universe like never before. Featuring the positions of the 4000 brightest and closest galaxies, alongside stunning real images of hundreds of them meticulously measured and oriented by hand, our app offers a unique window into the cosmic expanse. Delve into the depths of intergalactic space, where millions of galaxies beckon with their luminous allure, their distant light captured in mesmerizing astro-photographs. Embark on a journey of discovery and wonder as we unveil the mysteries of the cosmos. Through Cosmic Deepsky, may you find inspiration and awe in the boundless beauty that surrounds us, igniting a newfound appreciation for the magical universe we call home.

About

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.

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
Read full description

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.

Screenshots

Cosmic Deepsky4 screens
Messier Journal4 screens

Verdict

The call

The clearest difference is update cadence: Messier Journal at every 3 months against Cosmic Deepsky's every 23 months. Messier Journal also leads on price ($0.99 vs $2.99). Cosmic Deepsky's advantage is iOS requirement (15.0 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

CostPrice · In-app purchases · Ads · Monetization

Cosmic Deepsky costs $2.99 and Messier Journal $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for Cosmic Deepsky against 5.0 for Messier Journal. Both are backed by a comparable volume of ratings — 4 and 3 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

Cosmic Deepsky ships an update every 23 months, Messier Journal every 3 months. The most recent releases landed on October 13, 2026 and October 2, 2026 respectively.

Scorecard3 real differences · 7 level
Cosmic Deepsky versus Messier Journal: the parameters behind the verdict, then further details
ParameterCosmic DeepskyMessier Journal
Price$2.99$0.99 — better
Rating5.0 (4 ratings)5.0 (3 ratings)
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings4 — better3
Update frequencyEvery 23 monthsEvery 3 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better18.0
Further details — not scored
Size114 MB158 MB
Age rating4+4+
DeveloperCelestial Dynamics AGDamon Degner

Customer experience

Cosmic Deepsky

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Messier Journal

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Cosmic Deepsky

No in-app purchases

None

Messier Journal

No in-app purchases

Questions

Is Cosmic Deepsky free?
Cosmic Deepsky costs $2.99, with no in-app purchases.
Is Messier Journal free?
Messier Journal costs $0.99, with no in-app purchases.
Which has better reviews, Cosmic Deepsky or Messier Journal?
Cosmic Deepsky and Messier Journal are both rated 5.0 out of 5 on the App Store, from 4 and 3 ratings respectively.
Do Cosmic Deepsky or Messier Journal have ads?
Neither Cosmic Deepsky nor Messier Journal shows ads.
Which is updated more often, Cosmic Deepsky or Messier Journal?
Cosmic Deepsky ships an update every 23 months, and Messier Journal every 3 months. Most recently, Cosmic Deepsky was updated on October 13, 2026 and Messier Journal on October 2, 2026.

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