Comparison

Solar System Scope vs Monad Calendar Clock

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

Head to head
About

Solar System Scope

Explore and discover the solar system and outer space with realistic 3D visualizations and detailed celestial simulations. This app offers an educational and engaging experience for all ages, featuring a comprehensive encyclopedia and a night sky observatory.

Highlights
  • 3D Encyclopedia of celestial bodies
  • Realistic 3D visualizations
  • Night sky observatory with time simulation
  • Accurate orbital parameter calculations
  • High-quality planetary and moon maps
  • Multilingual support
Features
Read full description

Solar System Scope is a fun way of Exploring, Discovering and Playing with the Solar System and Outer Space. Solar System Scope (or just Solar) contains many views and celestial simulations, but most of all - it brings you closer to the furthest reaches of our world and lets you experience lots of fantastic space sceneries. It aspires to be the most illustrative, easy to understand and simple to use space model. - 3D Encyclopedia In Solar’s unique encyclopedia you will find the most interesting facts about every planet, dwarf planet, every major moon and more – and everything is accompanied by realistic 3D visualizations. Solar’s encyclopedia is available in 10 languages: English, Spanish, German, Russian, Italian, Korean and Slovak. More languages are coming soon! - Nightsky Observatory Enjoy Stars and constellation of the night sky as viewed from any given location on Earth. You can point your device at the sky to see all objects in their proper place, but you can also simulate Night sky in the past or in the future. Now with advanced options that let you simulate ecliptic, equatorial and azimuthal line, or grid (among other things). - Scientific Instrument Solar System Scope calculations are based on up-to-date orbital parameters published by NASA and let you simulate celestial positions at any given time. - For Everyone Solar System Scope is well suited for all audiences and ages: It is enjoyed by space enthusiasts, teachers, scientists, but Solar is successfully used even by children of 4+ years of age! - Unique Maps We are proud to present a very unique set of planetary and moon maps, that let you experience a true-color space as never before. These accurate maps are based on NASA elevation and imagery data. Colors and shades of the textures are tuned according to true-color photos made by Messenger, Viking, Cassini and New Horizon spacecrafts, and the Hubble Space Telescope. Basic resolution of these maps is for free – but if you would like the best experience, you can check out the highest quality, which is available with In-App purchase. - Join our vision Our vision is to build the ultimate space model and bring you the deepest space experience. And you can help - try Solar System Scope and if you like it, spread the word! And don’t forget to join the community and vote for new features on our homepage.

About

Monad Calendar Clock

This app visualizes time through planetary and celestial movements, contrasting natural rhythms with mechanical time. It offers unique perspectives on Earth's position in space and time, showing star and planet locations, seasonal changes, and lunar phases.

Highlights
  • Planetary time and date display
  • Celestial ring visualization
  • Heliocentric and Geocentric modes
  • Star and planet location tracking
  • Seasonal and lunar phase progression
  • Twilight and sunrise/sunset times
  • Event scheduling
Features
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MONAD does something that no other clock or calendar does; it tells the planetary time and date – the solar day, lunar month & seasonal year. MONAD reveals your unique place (and perspective) in planet-centered space and time. MONAD demonstrates the biorhythms of the Earth’s biosphere, and it integrates two types of time: 1) Natural time, which is cyclic, variable, and alive, with 2) Mechanical time, which is linear, highly regular, abstract and artificial. MONAD represents a paradigm shift of planetary proportions; A New Paradigm of Time With MONAD, you see the natural rhythms of time­ proceeding in endless circles and spirals. MONAD shows the location of the stars and planets; what’s visible at night from your location on Earth. MONAD shows the progression of the four seasons and the phases of the Moon; the obliquity of the ecliptic and the Earth’s circle of illumination, and a Twilight Dial tells you the time of Sun rise and Sun set at any latitude and time of year. MONAD shows the agricultural biorhythms of the Earth’s photosynthetic biosphere. MONAD restores the Earth, and the Earth’s biorhythms and biosphere, back to the center of our collective attention and awareness. With MONAD you see the Earth globe from an unusual perspective; the north (or south) polar axial perspective. MONAD automatically places a time zone-spanning Hour Hand at your location on the globe, marking your longitude & latitude, and you see all 24 time zones, all around the globe at the same time, the whole world interconnected. MONAD has four main Modes of operation. Geocentric (Geo) Mode features planet Earth at the center of a time and date-telling, 3-dimensional celestial ring. The algorithms and programming which drive all of the astronomical activity is based on a Sun-centered and highly accurate model of the solar system which you can access in Heliocentric (Helio) Mode. Accelerate through time, into the past or future, and watch how the configuration of the solar system changes. Shift back and forth from Geo to Helio Modes, and it’s easy to see how the two perspectives are related. It’s easy to see how and why the planets have apparent retrograde activity from an Earth-centered perspective. There is so much to explore and learn in MONAD. Astro Mode features a 2-dimensional Calendar-Clock face, which makes it possible to set the time by dragging the hour hand around the dial, or you can set the date by dragging the calendar band, or zodiac band, past the Sun’s meridian or date indicator fixed at noon at the top of the dial. A Table at the top of the screen lists the precise location of the Sun, Moon and planets at any time and date, so basically this Astro screen is equivalent to an astronomy or astrology chart, at any moment in time. Astro Mode will eventually feature a Scientific Astrology Program and an Educational Astronomy Program. Event Mode is where you record and schedule personal events, in the context of important and memorable planetary events we all share. Color-coded Event Wedges are shown in the context of the 4 corners of a solar day (Sun rise, noon, Sun set & midnight), the 4 corners of a lunar month (full and dark Moon, waxing and waning half Moons), and the 4 corners of a seasonal year (equinoxes & solstices). Another unique feature of MONAD is that you can record events “in the Now,” which encourages more presence in your life. A Health Event Mode allows you to see your personal, endocrine biorhythms in the context of planetary biorhythms we all share. The 24 hour circadian Calendar-Clock face is ideally suited to organize and display health events. If you choose to have MONAD integrate with the Apple Health app (HealthKit); then health data (e.g. Sleep period and Steps) read from HealthKit is used for display within the MONAD app. MONAD is beautiful, educational & transformative, and it will change the way you see the world around you, and your place within it. MONAD – A New Paradigm of Time.

Screenshots

Solar System Scope4 screens
Monad Calendar Clock4 screens

Verdict

The call

The clearest difference is review sentiment: Solar System Scope at 76% against Monad Calendar Clock's 22%. Solar System Scope also leads on price (Free vs $0.99) and rating (4.4 vs 3.7). Monad Calendar Clock's advantage is in-app purchases (none vs 1) and update cadence (every 6 weeks vs every 4 months). On ads, device support and iOS requirement 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

Solar System Scope is free to download; Monad Calendar Clock costs $0.99 up front. Solar System Scope sells 1 one-off in-app purchase. Monad Calendar Clock asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Solar System Scope holds the better App Store score, 4.4 against 3.7. That said, the two scores are not equally well evidenced: Solar System Scope has 882 ratings behind it against 14, so its average is the more settled of the two. Written reviews point the same way: 76% of Solar System Scope's written reviews are positive against 22% of Monad Calendar Clock's.

UpkeepUpdate frequency

Solar System Scope ships an update every 4 months, Monad Calendar Clock every 6 weeks. The most recent releases landed on September 22, 2026 and September 6, 2026 respectively.

Scorecard7 real differences · 3 level
Solar System Scope versus Monad Calendar Clock: the parameters behind the verdict, then further details
ParameterSolar System ScopeMonad Calendar Clock
PriceFree — better$0.99
Rating4.4 (882 ratings) — better3.7 (14 ratings)
Positive reviews76.4% of reviews — better22.2% of reviews
Number of ratings882 — better14
Update frequencyEvery 4 monthsEvery 6 weeks — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchases — betterPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.013.0
Further details — not scored
Size154 MB266 MB
Age rating4+4+
DeveloperINOVE, s.r.o.Earth at the Center LLC

Customer experience

Solar System Scope

All ratings882 ratings
Positive83.7%
Neutral4.5%
Negative11.8%
Written reviews237 reviews
Positive76.4%
Neutral6.3%
Negative17.3%

Monad Calendar Clock

All ratings14 ratings
Positive64.3%
Neutral7.1%
Negative28.6%
Written reviews9 reviews
Positive22.2%
Neutral11.1%
Negative66.7%

Bugs and requests

Solar System Scope

Reported bugs

4 issues
  • Crashes when dragging Jupiter
  • Upside-down orientation on tablets
  • Unable to restore purchases
  • Freezes and crashes on launch

Requested features

5 requests
  • Add more celestial bodies (Messier objects, Planet 9/10, black holes, etc.)
  • Enable exploration of other galaxies and deep space objects
  • Improve telescope/zoom functionality
  • Add more moons and irregular satellites
  • Implement continental drift and solar system evolution

Monad Calendar Clock

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

Solar System Scope

One-time1
  • HQ Textures / No Ads$5.99
None

Monad Calendar Clock

No in-app purchases

Questions

Is Solar System Scope free?
Solar System Scope is free to download, with in-app purchases available.
Is Monad Calendar Clock free?
Monad Calendar Clock costs $0.99, with no in-app purchases.
Which has better reviews, Solar System Scope or Monad Calendar Clock?
Solar System Scope is rated higher. Solar System Scope averages 4.4 out of 5 from 882 ratings, while Monad Calendar Clock averages 3.7 from 14 ratings.
Do Solar System Scope or Monad Calendar Clock have ads?
Neither Solar System Scope nor Monad Calendar Clock shows ads.
Which is updated more often, Solar System Scope or Monad Calendar Clock?
Solar System Scope ships an update every 4 months, and Monad Calendar Clock every 6 weeks. Most recently, Solar System Scope was updated on September 22, 2026 and Monad Calendar Clock on September 6, 2026.

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