Comparison

Monad Calendar Clock vs EarthPi

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

Head to head
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
Currently charting
Read full description

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.

About

EarthPi

Explore Earth with 27 interactive map projections. Visualize the planet from different angles, adjust time to see sunlight, and track celestial bodies. Save your discoveries with screenshot functionality.

Highlights
  • 27 Earth projections
  • Smooth projection transitions
  • Time control for sunlight simulation
  • Celestial tracking (sun and moon)
  • Screenshot functionality
Features
Read full description

EarthPi is a unique app designed to provide users with a detailed and interactive way to explore Earth through various map projections. With 27 distinct Earth projections, the app allows users to study and visualize the planet from multiple perspectives. Key Features: - 27 Earth Projections: Choose from a variety of Earth's map projections. - Smooth Projection Transitions: Switch between projections seamlessly with fluid animations and learn how each map projection works. - Time Control: Adjust the time to observe the dynamic interaction of sunlight with Earth’s surface across all projections. - Celestial Tracking: View the real-time positions of the sun and moon based on the selected time. - Screenshot Functionality: Capture and save images of any map projection. Future Development: The developer is dedicated to expanding EarthPi’s capabilities, with plans to introduce additional projections, features, and improvements.

Screenshots

Monad Calendar Clock4 screens
EarthPi4 screens

Verdict

The call

The clearest difference is price: EarthPi at Free against Monad Calendar Clock's $0.99. EarthPi also leads on review sentiment (67% vs 22%) and rating (4.5 vs 3.7). Monad Calendar Clock's advantage is in-app purchases (none vs 1) and chart position (#191 vs unranked). On ratings volume, update cadence, ads and device support 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

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

ReceptionRating · Positive reviews · Number of ratings

EarthPi holds the better App Store score, 4.5 against 3.7. Both are backed by a comparable volume of ratings — 14 and 16 respectively. Written reviews point the same way: 22% of Monad Calendar Clock's written reviews are positive against 67% of EarthPi's.

UpkeepUpdate frequency

Monad Calendar Clock ships an update every 6 weeks, EarthPi every 3 months. The most recent releases landed on October 29, 2026 and October 30, 2026 respectively.

Scorecard6 real differences · 5 level
Monad Calendar Clock versus EarthPi: the parameters behind the verdict, then further details
ParameterMonad Calendar ClockEarthPi
Price$0.99Free — better
Rating3.7 (14 ratings)4.5 (16 ratings) — better
Positive reviews22.2% of reviews66.7% of reviews — better
Number of ratings1416 — better
Update frequencyEvery 6 weeks — betterEvery 3 months
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
Best chart rank#191 — better—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.012.0 — better
Further details — not scored
Size266 MB116 MB
Age rating4+4+
DeveloperEarth at the Center LLCOthman Alzahrani

Customer experience

Monad Calendar Clock

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

EarthPi

All ratings14 ratings
Positive85.7%
Neutral0.0%
Negative14.3%
Written reviews3 reviews
Positive66.7%
Neutral0.0%
Negative33.3%

In-app purchases

None

Monad Calendar Clock

No in-app purchases

1 purchases

EarthPi

One-time1
  • EarthPi Premium$3.99

Questions

Is Monad Calendar Clock free?
Monad Calendar Clock costs $0.99, with no in-app purchases.
Is EarthPi free?
EarthPi is free to download, with in-app purchases available.
Which has better reviews, Monad Calendar Clock or EarthPi?
EarthPi is rated higher. Monad Calendar Clock averages 3.7 out of 5 from 14 ratings, while EarthPi averages 4.5 from 16 ratings.
Do Monad Calendar Clock or EarthPi have ads?
Neither Monad Calendar Clock nor EarthPi shows ads.
Which is updated more often, Monad Calendar Clock or EarthPi?
Monad Calendar Clock ships an update every 6 weeks, and EarthPi every 3 months. Most recently, Monad Calendar Clock was updated on October 29, 2026 and EarthPi on October 30, 2026.

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