Comparison

Emerald Chronometer vs Planetary Hours

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

Head to head
About

Emerald Chronometer

Experience highly detailed mechanical watch faces with advanced astronomical and clock complications. Track celestial events, manage time with precision, and explore historical and future dates with interactive displays. Optimized for iPhone and iPod touch.

Highlights
  • Accurate astronomical data (4000 BCE - 2800 CE)
  • Sun, Moon, and planet rise/set times
  • Mechanical display of Moon phases
  • Precise local and UTC time
  • Chronograph with split timer
  • World-time and calendar watches
  • Interactive time-travel simulation
Read full description

These models of high-end mechanical watch faces contain many of the most complex "complications" found in real watches, plus refinements found nowhere else. All displays maintain the look and feel of real mechanical objects, but with the time and location accuracy of the iPhone. NOTE: This app (Emerald Chronometer) is optimized for the iPhone and iPod touch. Please also see Emerald Chronometer HD, a separate product optimized for the iPad. Astronomy features: - Highly accurate data from 4000 BCE to 2800 CE - Times of rise and set for the Sun, the Moon, and the 5 classical planets - The correct shape and orientation of the Moon in all phases but still using a mechanical display - Relative positions of the Sun, Moon, 6 planets and the constellations of the zodiac - "Compass functions" show the elevation and azimuth of the Sun, the Moon, and the 5 planets - The Equation of Time, solar time and sidereal time - Eclipse predictor (lunar node indicators and separation indicator) - User settable geographic location and timezone using an 80,000 city database - A unique face showing the rise and set times of all 5 classical planets plus the Sun and the Moon at once Clock features: - Day/date/month/year indicators, using mechanical wheels - Local and UTC time - Chronograph (stopwatch) with split timer, 1/10 sec accuracy - Alarm clock and interval timer; notifications are delivered in iOS 4 if the app is not running** - World-time watch with 24-city ring on one side and 4 subdials on the other - Calendar watch with rotating wheels showing a full month at a time - Most watches with 1/5 sec or 1/10 sec precision - Synchronized with standard atomic clocks via NTP There are 16 watches in all, with 27 total watch faces (including front and back sides). A setting is available to allow the display to stay on only when plugged in. Play with the watches by tapping on the crown and moving the hands, or press and hold on a date window to zoom through time to see the effect on the heavens. Then just use them to show you when it's time for a break. A complete description of each application feature can be found in the built-in Help screens and on the Emerald Sequoia LLC Web Site, which also includes a demo movie. A developer's blog may also be found at http://emeraldsequoia.com/esblog/ . If you are having any trouble with the application whatsoever, please see our FAQ on the support page listed below and then contact us through that page if your problem is not resolved. We take pride in responding promptly to all support email requests. **NTP accuracy is not guaranteed for alarm delivery if the app is not running. (NTP requires Internet access. Like all apps Emerald Chronometer can not change the device's internal clock.)

About

Planetary Hours

This app provides a dynamic clock that displays planetary hours, adapting to the natural flow of the sun. It offers real-time calculations based on your location and supports various iOS features like Live Activities and Apple Watch complications for at-a-glance timing updates.

Highlights
  • Dynamic Island & Live Activities
  • Apple Watch Complications
  • StandBy & Lock Screen Widgets
  • Interactive Home Screen Widgets
  • Precision Astronomy Calculations
  • Offline Processing
  • Customizable Notifications
Features
Read full description

Unlock the ancient rhythm of time with Planetary Hours. Unlike standard mechanical clocks, planetary hours adapt to the natural flow of the sun, dividing day and night into unequal segments ruled by the seven classical planets. Whether you practice electional astrology, planetary magic, or simply wish to align your schedule with cosmic rhythms, this app is your precision tool. EXCLUSIVE iOS FEATURES We leverage the full power of your device to keep you in sync without opening the app: Dynamic Island & Live Activities Track the current planetary ruler and remaining time instantly from your Lock Screen or Dynamic Island. Never miss a transition again. Pro Apple Watch Experience • Complications: Rich data on your wrist. See the current planet, symbol, and countdown directly on your favorite watch face (Modular, Infograph, Circular supported). • Standalone App: Fully functional on Apple Watch, no iPhone needed nearby. StandBy & Lock Screen Widgets Turn your iPhone into a magical altar clock at night. Our StandBy widgets look stunning on your nightstand, while Lock Screen widgets give you at-a-glance timing updates. Interactive Home Screen Widgets Beautiful, data-rich widgets that adapt to Light and Dark mode. View the current hour, next transition, and day/night progress directly from your Home Screen. CORE FEATURES • Precision Astronomy: Real-time calculation based on your exact GPS coordinates and local sunrise/sunset. • Chaldean Order: Accurate sequence for all 7 classical planets (Saturn to Moon). • Privacy First: All calculations happen offline on your device. No tracking, no data collection. • Notification System: Get notified exactly when the planetary hour changes. Download now to synchronize your life with the solar rhythm.

Screenshots

Emerald Chronometer4 screens
Planetary Hours4 screens

Verdict

The call

The clearest difference is price: Emerald Chronometer at Free against Planetary Hours's $4.99. Emerald Chronometer also leads on rating (4.9 vs 4.0) and ratings volume (122 vs 1). Planetary Hours's advantage is update cadence (monthly vs every 22 months). On review sentiment, in-app purchases, monetization model 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

Emerald Chronometer is free to download; Planetary Hours costs $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Emerald Chronometer holds the better App Store score, 4.9 against 4.0. That said, the two scores are not equally well evidenced: Emerald Chronometer has 122 ratings behind it against 1, so its average is the more settled of the two. Written reviews complicate that: 97% of Emerald Chronometer's written reviews are positive against 100% of Planetary Hours's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Emerald Chronometer ships an update every 22 months, Planetary Hours monthly. The most recent releases landed on November 6, 2026 and November 5, 2026 respectively.

Scorecard5 real differences · 5 level
Emerald Chronometer versus Planetary Hours: the parameters behind the verdict, then further details
ParameterEmerald ChronometerPlanetary Hours
PriceFree — better$4.99
Rating4.9 (122 ratings) — better4.0 (1 ratings)
Positive reviews96.8% of reviews100.0% of reviews — better
Number of ratings122 — better1
Update frequencyEvery 22 monthsMonthly — better
Ads—No
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, Apple Watch
Requires iOS15.0 — better17
Further details — not scored
Size311 MB16 MB
Age rating4+4+
DeveloperScapa Flow, LLC雪 蔺

Customer experience

Emerald Chronometer

All ratings96 ratings
Positive97.9%
Neutral1.0%
Negative1.0%
Written reviews63 reviews
Positive96.8%
Neutral3.2%
Negative0.0%

Planetary Hours

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Emerald Chronometer

No in-app purchases

None

Planetary Hours

No in-app purchases

Questions

Is Emerald Chronometer free?
Emerald Chronometer is free to download, with no in-app purchases.
Is Planetary Hours free?
Planetary Hours costs $4.99, with no in-app purchases.
Which has better reviews, Emerald Chronometer or Planetary Hours?
Emerald Chronometer is rated higher. Emerald Chronometer averages 4.9 out of 5 from 122 ratings, while Planetary Hours averages 4.0 from 1 ratings.
Which is updated more often, Emerald Chronometer or Planetary Hours?
Emerald Chronometer ships an update every 22 months, and Planetary Hours monthly. Most recently, Emerald Chronometer was updated on November 6, 2026 and Planetary Hours on November 5, 2026.

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