Support & help — for Eclipse: Solar & Lunar Sky on iPhone, iPad and Android, and the browser version at eclipse.alokm.com. Same app, same code.
Something wrong, or an idea for the app? Write to me — I read everything.
It helps to say which device and which version you are on, and — for anything about times or visibility — which eclipse and which place the app was set to.
Never look at a partially eclipsed sun without a proper solar filter. Sunglasses, smoked glass, exposed film and looking through a camera, binoculars or a telescope are all unsafe, and the damage is painless while it happens. Only the brief moments of totality — when the sun's disc is completely covered, and only then — can be watched with the naked eye.
The app's Learn → Protect your eyes page goes through what is safe, and how to project the sun instead of looking at it.
That is an answer rather than a fault. A total or annular eclipse is only total or annular along a narrow track, often a few hundred kilometres wide, and outside it the eclipse may be partial or nothing at all. From any one place, an eclipse of some kind is a once-every-few-years event.
To find the ones you can see, open the eclipse chooser and turn on Visible here: it tests every eclipse in the date range against your location and lists only those where one actually happens above your horizon.
Times are shown in your device's time zone — the abbreviation is printed next to the coordinates, so you can always see which one is being used. For an eclipse near you that is what you want. For one on the other side of the world it can read as an odd hour, or even the day before or after.
So a Chilean eclipse looked up from a phone set to India is printed in Indian time. Change the device's time zone and the same eclipse reads in local terms.
Location is optional and the app never insists. Tap the place name at the top and search the built-in city list, or tap the map to drop a pin — the city list ships inside the app, so it works with no network at all, as does the astronomy, the globe and everything else bar the detailed map you reach by zooming right in.
On iPhone and iPad the permission is asked for only when you tap use my location; opening the app never prompts. On Android the app asks once on first run, and you may refuse and pick a city instead.
That is a set on the globe: the app opens on a preview of the eclipses nearest today, and the Saros view and the chooser can each put a group up there deliberately. The header names the set and its date range rather than a single eclipse.
To get back to one: tap any path on the globe to focus that eclipse, pick one from a list, or use the ✕ Set button at the top left of the globe. The app remembers which way you left it.
On iPhone and iPad, for now. Shared links open eclipse.alokm.com in the browser, which shows exactly the same view — the same eclipse, seen from the same place. On Android the link opens the app itself. Doing that on iOS is on the list.
Every new and full moon in the catalog, in sequence, wrapped into rows as long as a cycle you choose — an eclipse year, a synodic year, a calendar year, or a length you set yourself. Eclipses only happen when a new or full moon falls near a node of the Moon's orbit, so wrapping the sequence by the right cycle pulls those moments into line and the eclipse seasons show up as a band running down the lattice.
Tap any mark to jump to that line-up. The ‹ › arrows step through them one at a time, or by month or by a whole eclipse cycle, and holding one down sweeps.
Eclipse predictions by Fred Espenak, NASA's GSFC. The app computes local circumstances from the Besselian elements of each eclipse, on your device.
Contact times are geometric: they assume a flat horizon at sea level and take no account of hills, buildings or your height above the ground, all of which move the real event by more than the arithmetic ever will. Near the very edge of a path, where totality lasts seconds, treat the numbers as an invitation to move further in.
The app does its work on your device. There is no account, no advertising, no in-app purchases and no server of mine, and nothing about you is collected or logged. The one thing that leaves your device is the detailed map you reach by zooming in — from Google on Android, from Apple on iPhone and iPad — which is a request for that patch of ground, made to them and not to me. The full policy is here.