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Emerald Chronometer Support


Version 3.9.3 crashes on iOS 7!
This is a known problem with Emerald Chronometer v3.9.3 and v3.9.3.4 on iOS 7. Upgrading to v3.9.4 (now available) will fix the problem.

Local Notifications that pop up when Emerald Chronometer is not running are sometimes missing sounds!
This was an issue with iOS 9.x releases prior to iOS 9.1. Upgrading to iOS 9.1 should fix this problem.

All I see is a black screen!
This is a known problem with Emerald Chronometer v3.9 on iOS 8. Upgrading to v3.9.2 (now available) will fix the problem.

In landscape mode in Emerald Chronometer HD, it's off-center and some things are missing!
This is a known problem with Emerald Chronometer HD v3.9.1 on iOS 7. Either upgrade to iOS 8 or download ECHD 3.9.2 (now available).

I just see one watch and it's nothing like the screen shots on the App Store®.
Swipe left or right to see the others. Tap the "i" button to read the help files. Or click here.

I'm seeing crashes (Emerald Chronometer just abruptly disappears or hangs).
That was a frequent occurrence for many apps with early versions of the iPhone OS. If you're not running the latest version:
then upgrading may well fix it. And, of course, make sure you're using the latest version of Emerald Chronometer (at least 3.0). If you see a crash with the latest versions of Emerald Chronometer and iOS, and you're not running a jailbroken phone (see below), PLEASE report it to the email address below.

That said, in many cases, it will work if you just try again. You may have to turn the iPhone's power off and back on (hold down the sleep/wake button for a few seconds until you get the power off message). You may have to do this twice. If that doesn't fix it, the next step is to remove the app and download it again. Despite appearances, this will be free. Here are Apple's instructions for reloading an app:
It may be important to restore the app with iTunes® not with the App Store app on the phone itself. If your iPhone is nearly full (i.e. less than 10% free space as reported at the bottom of your phone's Info tab in iTunes) that may also cause problems. For additional tips that might help see:

Please contact us at the email address below if none of these suggestions help. We'll do our best to resolve your problem.

When a Local Notification is fired for an alarm when the app is in the background, the sound keeps going even after I dismiss the dialog.
This problem occurred on iOS 4.2 but was fixed with iOS 4.2.1 and iOS 4.3. Updating your device to the latest OS should fix the problem.

The alarm doesn't work if Chronometer is in the background or if the screen is locked (iOS 5 or later).
Go to the Settings app, choose the Notifications item on the left side, and scroll down on the right side until you see "Chronometer". Tap on it and then turn on the switch for "Sounds". That will allow the alarm sound to play even when Emerald Chronometer is not active.

Why did the app size increase so dramatically with Emerald Chronometer version 3.3?
Because of the larger artwork needed for the Retina display. For more details, see our blog entry about this.

The documentation claims it shows moonrise and set times but I don't see that anywhere.
Many features appear only on the "back" side of a watch. Click the button on the lower left corner of the screen to switch sides. (The moon rise/set info is on the backs of Haleakala and several others.)

Sometimes I see a miniature version of the watch for a second and it says "Loading". What does that mean?
It means we're reading the data describing that watch from secondary storage. That takes a while. We don't have enough RAM to keep all the watches loaded at once. We keep as many loaded as possible but if you swipe very quickly you can get ahead of our loader.

Firenze's back and the other watches don't seem to agree about rise and set times.
Right. And the Help is not entirely correct about when the planets are visible with respect to the horizon mask. Because Firenze only has a single horizon indicator for all of the planets (we use "planet" to refer to the Sun and Moon too, in this context), it is only a rough indication for any particular planet and can be wrong in certain situations; use Miami if you want precise information. Specifically, the horizon indicator shows only the azimuth of the intersections of the ecliptic plane with the horizon, and thus is only exact when read against the Sun hand (or against another planet's hand if the planet happens to lie exactly in the plane of the ecliptic). If the planet is outside the ecliptic plane (that is, if its ecliptic latitude is nonzero), then the horizon indicator for that planet can be wrong in two circumstances:
  * Close to the time of rise or set
  * Close to the time when the ecliptic plane passes through the zenith, as it does in tropical latitudes.
So the bottom line is that the horizon mask should be taken as a rough guide only. Use Miami if you want more precise info.

Mauna Kea shows the Sun in Cancer on Aug 3 but Cancer is June 23 – July 22.
It's because of the precession of the equinoxes and the inaccuracy of the calendar prior to the Gregorian Reform of 1582. Mauna Kea's zodiac dial shows the present astronomical positions of the constellations which have changed considerably from their positions when the astrological dates were fixed in ancient times. If you set the date back to about 600 BCE the constellations will be more closely aligned with the astrological dates.

But Mauna Kea doesn't seem to quite match the astronomical constellations, either.
Right. MK divides the zodiac into twelve equal sections and labels each one with a constellation. The actual constellations are not all the same size, so MK's labels are only approximate. The numbers in between each constellation label, however, do accurately indicate right ascension (measured in hours). Geneva's back side shows the actual constellation boundaries (for the present epoch).

Will it work on an iPod® touch?
Versions 1.1 and newer support the iPod touch. But see here for more about setting your time and location correctly.

Will it work on an iPad®?
Yes. It will work just as it does on the iPhone, in emulation mode. For the full iPad experience download Emerald Chronometer HD.

It doesn't look quite the same on my iPhone 4 as the pictures on the website.
Right. There are separate high-resolution graphics for the Retina display. Here's an example.

Will Emerald Chronometer work without an Internet connection (eg. out in the wilderness where even cell phone service is unavailable)?
Yes. Time and location are all that we need; all of the astronomy calculations are done internally with no Internet required. See here for more about setting your time and location correctly.

The sunrise/sunset times are wrong on my iPod touch.
You may need to enter your latitude and longitude manually. You do this via the Settings panel which is accessed from the "gear" button in the lower right corner of the screen. See here for more details.

Will it work on a jailbroken iPhone?
Probably not. We don't support that configuration and we've had reports of odd problems.

What's all this about "complications"? What's so complicated about a little calculation?
Well, the calculations are actually pretty complex. But "complication" is a term of art in the horology (fancy watch) world. It refers to any watch display other than hours, minutes, and seconds (or sometimes simple day/date). See:
Emerald Chronometer has a very large number of complications; here's a list.

The times for moonrise and moonset are not consistent between the various watches.
Emerald Chronometer uses different rules for the "ring"-type displays like Mauna Kea and for the "dial"-type displays like Haleakala:

The "dial"-type displays use rise and set times for the current day (i.e. the day shown in the date windows), except in cases when the event doesn't happen on that day in which case it just displays 00:00 (this happens a couple times a month for the Moon and in summer and winter at high latitudes for the Sun). The values are updated at midnight.

On the "ring"-type displays, we use a more complicated algorithm but the result is simpler. The rings show the closest rise and set time to the current time without regard to the day or whether that's before or after the current time. (In detail: if the Sun is above the horizon then the sunrise indicator shows the time of the previous sunrise and the sunset indicator shows the next sunset; but if it's nighttime then the sunset indicator is shows the time of the last sunset and the sunrise indicator shows the time of the upcoming sunrise. The sunrise time is updated at sunset and vice versa. Similarly for the Moon.)

Since the times of sunrise and sunset change by only a few minutes per day the differences between the two rules are small. But the times of moonrise and moonset change by about an hour each day so the differences are readily apparent.

Mauna KeabothRingnext/prev
HaleakalabothDialfor day
GenevafrontDialfor day
MiamibackDialfor day

I set Haleakala's time to the exact time of sunrise but the altitude hand is a little below zero.
Yes, that's right. Sunrise is defined to be the time at which the first bit of the Sun's disk is visible. But the Sun's altitude is defined as the altitude of the center of the disk. It takes several minutes for the Sun to move that far.

I have a real watch that displays the Equation of Time. It shows a value that's not the same as yours.
We adopt the convention that a positive number means the sundial will show a later time than an ordinary clock. IE:
      EOT = sundial time - standard time
Some watches use the opposite convention. Learn more about the Equation of time here:

I leave my iPhone in its dock to charge and love to see my watches all the time. But how can I do that without disabling Auto-lock completely?
Emerald Chronometer has two settings that allow you to disable Auto-lock while it is running: one that applies when the device is plugged in and another that applies when running on battery power. Be careful with the second one; it can drain the battery in just a few hours. See here for more details.

I set an alarm and quit Emerald Chronometer but when the alarm time came no alarm rang. This works fine with the builtin Clock and Calendar apps.
In iOS 4 and above, Emerald Chronometer will deliver a local notification in this case. If your phone can't run that OS because it's too old, there's nothing we can do for you; in older OSs, Apple didn't allow any third party apps to do anything in the background.

When my alarm goes off when the screen is locked shaking doesn't silence it.
Yes. Apple disables the accelerometers when the screen is locked. We have no control over this. The alarm will stop when you unlock the screen.

I set an alarm and left Emerald Chronometer running but when the appointed time arrived in the morning there was no sound.
In some cases with the iPod touch the volume gets reset to zero. After considerable research one of our customers (using OS 3.1.2 on a new iPod touch) describes it this way: "I now suspect a flaw in Apples's software. If Calendar or Mail prefs call for no sound and an event occurs, the apps instruct iPod's master volume to set to zero. Since other apps assume the volume is previously set as the user wishes, no sound is subsequently produced when those apps trigger an event. No doubt the unintended consequence of the new coding necessary to accommodate the physical volume controls....I have been able to confirm that no non-apple alarm clocks function, now. The OS is buggy in the sound department. Forums are full of complaints about all kind of sound issues."

When I start up Emerald Chronometer sometimes the hands jump just as the time synchronization indicator turns green.
Yup. Until we get the first reply from an NTP server we don't really know what the right time is. It will be stable after that.

My eyes aren't what the used to be and some of those dials and hands are awfully small. Can you implement a zoom feature?
Recent iPhone and iPod touch models have a way to do a zoom on any app. Go to Settings=>General=>Accessibility and click on Zoom. The zoom gestures are explained on that page. If you don't find this setting, make sure you have the latest iPhone OS.

Why is it asking to use my location?
Emerald Chronometer needs to know your location in order to compute various astronomical quantities (eg. sunrise time). That's all we use it for. The data is stored on your device only. We do not transmit it anywhere. We do not sell it to anyone. We update it each time the app starts up and about once an hour thereafter. It will be copied to your computer when you sync with iTunes so you may want to encrypt your backups.

Since I bought Emerald Chronometer, I've started getting spam about watches!
Emerald Sequoia has not ever sold, nor will we ever sell, email addresses of our customers or of anyone else who contacts us via email. We hate spam as much as you do.

I'd love to have Emerald Chronometer running on an iPod nano, say with a TikTok or LunaTik watch band.
We'd love that too! But unfortunately Apple doesn't allow third-party developers to write apps for the nano; it's not running iOS like the iPhone and iPod touch.

If and when Apple does open up the nano to third-party apps, you can be sure we'll be taking a look....

It sure would be nice if ...
Don't hesitate to send us enhancement requests or ideas for new watches. Some of the ideas we've gotten have been really interesting! We're only a two-person company, so we can't promise if or when any particular request will be implemented. But the more requests we get from our customers for a particular feature the higher its priority becomes. Unless we think it's really cool and do it right away. smiley

The iPhone isn't designed for the wrist! How can I get the full experience of actually wearing a fine mechanical timepiece?
If you're desperate, you could try this.  But we don't recommend it. :-)

Update 2018 Apr 18: If you have a watch running Wear OS by Google (this doesn't include Apple Watches, unfortunately), you can buy our app(s) for that platform!

I thought upgrades were free but the App Store seems to have no option other than "Buy Now".
Yes, that's a bit odd. But it really is free. Just click the "$4.99" button and the "Buy Now" button and enter your password. After a bit you'll see a message saying, "You have already purchased this item. To download it again for free, select OK."

I tried to upgrade to the latest version and got a message saying I needed to pay again. I thought the upgrades were free?
This is most likely the result of a mix up in your iTunes configuration. It probably doesn't recognize you as the one who bought the original version, perhaps because you have more than one iTunes account.

It may also be that the account you used with the App Store app on your iPhone is not the same as the one you're using with iTunes. If so, and you don't want to change that, then just get the upgrade directly on your iPhone via the App Store application.

I want my money back <for whatever reason>
Unfortunately, Apple does not provide developers like us a way to refund or annul a purchase, as far as we've been able to discover. One thing that may work, though, is to use the iTunes® store feedback process described at
One of the great benefits of the way Apple set up the iPhone application distribution system is that developers don't have to get involved in the billing process. One of the negatives is that we have no direct way to help even if we want to.


We work hard to make Emerald Chronometer as close to perfect as we can. But we're realists. And we're here to help. So if you have a problem just send mail to
Please read the documentation and check the FAQs first. Make sure you have the latest version (see the Release Notes); it's displayed at the bottom of each Help screen. We try to respond quickly but we're only a two-person company so occasional delays are inevitable.


We would also very much appreciate any comments you may have about how we can improve Emerald Chronometer in the future. In particular, we will be making more watches. We would love to hear your ideas. Use the email address above.

Release Notes

Click here to see what's changed in each release.

Copyright © 2011, Emerald Sequoia LLC; last updated: 2015 Mar 1

Apple, iTunes, App Store, iPhone and iPod are trademarks of Apple Inc.