iPad Screenshots


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 HD) only works on the iPad. Please also see Emerald Chronometer, a separate product optimized for the iPhone and iPod touch. The products have exactly the same watches and are identical except that this HD product has the ability to rotate the display, increased resolution on the watches, and larger settings panels.

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
- Most watches with 1/5 sec or 1/10 sec precision
- Synchronized with standard atomic clocks via NTP

There are 15 watches in all, with 26 total watch faces (including front and back sides).

The app works equally well in landscape mode and portrait mode, and 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. Like all apps Emerald Chronometer can not change the device's internal clock.)

What’s New

Version 3.10.1

- Support for Dark Mode
- Support for iOS 15

Ratings and Reviews

5.0 out of 5
9 Ratings

9 Ratings

ssilverblack ,

instant analog IT fan - astronomy v astrology

As a many-decades expert of both Information Technology, and privately as an Astrologer, went looking recently for an analog equivalent summary of datetime for casual glances at an iPad while working on a Windows laptop in languages Python and R. R of course is Linear Algebra, which in Western 'science' was borrowed very recently in the 19th Century from Babylonian and Chinese matrix mathematics circa 100 BCE. Similarly, Astrology was the root knowledge modern Astronomy dervied from, and similarly neither has gone away today. The analog depictions in the current App are fun, a few touch on the eye-visible 7 traditional planets, however use rise / set Geocentric visible times for location v. Astrological Asc / Desc calculations.

What could be added? (1) Pluto, Neptune, Chiron, Uranus, the Nodes of the Moon. (For full Astrological calculations, depictions, see AstroGold for comparison.) (2) Add also a Settings switch between contemporary astronomical Zodiac calculations (which drift over time), or optionally Astrological Zodiac (30 degrees each, 12 signs, positions set to fixed reference roughly 2000 years ago).

Fun! -reminder everything we do with digital hand-held devices has roots in the Real World, get grounded now!

JhollJr ,

It’s Complicated

I’ve used the “Chronometer” for iPad and for iPhone for years and visit the various faces everyday. My favorite is the Geneva, because there is just so much information there. I really wish there were a face for the Apple Watch, but I understand that Apple has restrictions. I wish it could be worked out somehow, because there aren’t any more beautiful watch faces for astronomy lovers than the ones that the Chronometer shows. I tried buying a watch that ran WearOS, but the experience just wasn’t as good as the Apple watch. So I went back to the Apple Watch and just visit the Chronometer faces on my iPhone and iPad.

WhatNowHuh ,


Amazing. We all have preferences for how some things should be different, feature requests, and so on, but the only real hope I have is that this will stay compatible with the upcoming OS releases in at least the foreseeable future.

App Privacy

The developer, Emerald Sequoia LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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