Comparison

Daimyo Clock vs Citizen Sky View

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

Head to head
About

Daimyo Clock

Experience traditional Japanese timekeeping with this app, which recreates a 17th-century mechanical clock. It accurately displays time divided into six equal periods for day and night, adjusting for seasonal changes in daylight.

Highlights
  • Traditional Japanese timekeeping
  • Day/night divided into six equal periods
  • Seasonal daylight adjustments
  • Accurate solar noon calculation
  • Location-based time display
  • Twilight start/end calculation
Read full description

Daimyo clock is a recreation of a mechanical clock developed in the seventeen century based on western clocks but modified to show traditional Japanese time. Traditional Japanese time divides the day and night into six equal periods from dawn to dusk and dusk to dawn respectively. Over the course of a year as the daylight and nighttime periods lengthen and shorten, the length of these six day or night periods change. Unlike Western clocks which are regulated by a single pendulum and run at a constant speed day or night, Japanese clocks incorporated two pendulums, and switched between them at dawn and dusk. Adjustment for the changing daylight and nighttime hours was accomplished by adjusting the effective length of the pendulums, normally done every two weeks, or twenty-six times a year. This kept the time shown on the clock reasonably close to the correct time, provided that the clock had been set correctly initially. This modern implementation is much more accurate and precise than the original clocks. In this implementation, the biweekly adjustments of the mechanical clock are made continuously, thus the day or night period length are always correct. Noon on the clock will, if location services are enabled, occur when the sun is at the zenith, or solar noon. Day start and end correspond to the beginning or end of twilight, and are calculated accounting for the refraction of the Earth's atmosphere. There are three situations where the clock my not show the local time in the Japanese manner: 1. If location services are off, Daimyo Clock will show the time for Tokyo, Japan. 東京 will be displayed on the clock face in this case. 2. While the application is obtaining an updated location after launch or returning to foreground. 3. Near the North or South poles the sun may either be above the horizon or below it for the entire day (24 hour period). In this case, the Japanese definition of time no longer applies, so the clock face will be shown without a clock hand.

About

Citizen Sky View

Participate in a NASA-sponsored citizen science project to study cloud formation. Coordinate with the project team for events, then use your phone to capture images of the sky at assigned locations and times. Your contributions help researchers learn more about atmospheric science.

Highlights
  • Citizen science participation
  • Cloud formation research
  • Event coordination
  • Location-based image capture
  • Data contribution for research
Features
Read full description

This application is for a citizen science project being developed at the University of Colorado at Boulder. It is sponsored by NASA and NCAR. The project requires you to coordinate with the project team to attend our upcoming events where you will be assigned a location to be at a specific time. During the event, you will have oriented your phone and placed it upside down so that it can take pictures every 30 seconds until the event is over. The team will then take these images to learn more about cloud formation.

Screenshots

Daimyo Clock2 screens
Citizen Sky View4 screens

Verdict

The call

The clearest difference is rating: Citizen Sky View at 5.0 against Daimyo Clock's 4.0. Citizen Sky View also leads on update cadence (every 2 weeks vs every 37 months) and iOS requirement (10.3 vs 16.0). On price, ratings volume, ads and in-app purchases 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Citizen Sky View holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

UpkeepUpdate frequency

Daimyo Clock ships an update every 37 months, Citizen Sky View every 2 weeks. The most recent releases landed on October 4, 2026 and October 9, 2026 respectively.

Scorecard3 real differences · 7 level
Daimyo Clock versus Citizen Sky View: the parameters behind the verdict, then further details
ParameterDaimyo ClockCitizen Sky View
PriceFreeFree
Rating4.0 (1 ratings)5.0 (1 ratings) — better
Positive reviews100.0% of reviews—
Number of ratings11
Update frequencyEvery 37 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPad, MaciPhone, iPad, iPod
Requires iOS16.010.3 — better
Further details — not scored
Size1 MB26 MB
Age rating4+4+
DeveloperDouglas HildumUniversity of Colorado Boulder

Customer experience

Daimyo Clock

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Citizen Sky View

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Daimyo Clock

No in-app purchases

None

Citizen Sky View

No in-app purchases

Questions

Is Daimyo Clock free?
Daimyo Clock is free to download, with no in-app purchases.
Is Citizen Sky View free?
Citizen Sky View is free to download, with no in-app purchases.
Which has better reviews, Daimyo Clock or Citizen Sky View?
Citizen Sky View is rated higher. Daimyo Clock averages 4.0 out of 5 from 1 ratings, while Citizen Sky View averages 5.0 from 1 ratings.
Do Daimyo Clock or Citizen Sky View have ads?
Neither Daimyo Clock nor Citizen Sky View shows ads.
Which is updated more often, Daimyo Clock or Citizen Sky View?
Daimyo Clock ships an update every 37 months, and Citizen Sky View every 2 weeks. Most recently, Daimyo Clock was updated on October 4, 2026 and Citizen Sky View on October 9, 2026.

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