Italian Six-Hour Clock · iOS
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Six-hour periods anchored to solar events — Primo, Secondo, Terzo, and Quarto — rather than clock midnight.
Live sun position, lunar phases, moonrise and moonset times, moon altitude and direction, and constellation boundaries.
Notifications for all hours of the Divine Office — Matins, Lauds, Prime, Terce, Sext, None, Vespers, Ave Maria Bell, Sunset, and Compline — calculated astronomically.
Default, USA 250th Anniversary, and Vatican color schemes. Your choice is saved automatically.
Novus Ordo or Vetus Ordo Form, updated daily. Solemnities, feasts, obligatory and optional memorials displayed in priority order.
Daily Luna age as announced at Prime in the Roman Martyrology, together with the Roman calendar date, Golden Number, and Epact — computed from the Gregorian computus of Clavius.
Precise solar calculations for your exact latitude and longitude. Works offline using your last known location.
These are the four periods of the traditional Italian clock, which divides the day into four six-hour watches anchored to sunset and sunrise rather than clock midnight:
The 30-minute offset reflects the traditional ringing of the Ave Maria bell at sunset, which marked the start of the new period. All times shift daily with your local sunrise and sunset.
Below the clock face you will see a line identifying today in the Roman liturgical calendar — for example, Saint Thomas Aquinas, Priest and Doctor or Tuesday of the 3rd Week of Lent. The app follows this priority: solemnities and feasts are shown first, then obligatory memorials, then optional memorials, and finally a ferial (weekday) description based on the current liturgical season and week.
You can choose between the Novus Ordo (General Roman Calendar, 1969) and the Vetus Ordo (Roman Missal of 1962) in About → Liturgical Calendar.
The Clock tab displays three lines of traditional computus information beneath the next canonical hour:
All values are computed from the Gregorian computus of Christopher Clavius, as mandated by Pope Gregory XIII in 1582 and described in the Romani Calendarii Explicatio.
Tap the ⓘ button in the top-right corner of the Clock tab to open the About sheet. Under Explore, tap Liturgical Calendar and select your preferred form. The Clock tab label updates immediately. Your choice is saved and remembered across app launches.
Tap the ⓘ button in the top-right corner of the Clock tab to open the About sheet. Under Explore, tap Themes to choose between Default, USA 250th Anniversary, and Vatican color schemes. Your choice is saved automatically and applies throughout the app.
The app uses your location (latitude and longitude) to compute the precise times of sunrise, solar noon, sunset, and twilight events for each day using a high-accuracy solar position algorithm (accurate to within one or two minutes). From those anchors it derives each canonical hour:
The Sky Map tab displays a polar projection showing the sun's current position relative to your location, along with constellation boundaries. It also shows lunar information including the current moon phase, moonrise and moonset times, moon altitude and direction, distance from Earth, and upcoming New Moon and Full Moon dates. All calculations are performed on-device using high-precision astronomical algorithms.
Compline is calculated as three hours before solar midnight (the midpoint between solar noon and the next solar noon). This traditional timing places the final prayer of the day late in the evening, anchored to astronomical rather than clock time.
No problem. If you decline or later revoke location access, the app will ask you to type in a city name or zip code. It uses that to look up coordinates and calculate solar events for your chosen location. The app also remembers your last known location, so solar times remain available even if you open the app offline. You can tap Open Settings inside the app at any time to re-enable location access.
Check that your iPhone is not in Silent Mode (the physical mute switch on the side). Also confirm that notifications are enabled for Ave Maria Clock in Settings → Notifications → Ave Maria Clock, and that Sounds is turned on there. If the issue persists, try toggling the event off and back on in the app's Notifications tab.
Yes, for Matins, Vespers, Ave Maria Bell, and Compline. On the Notifications tab, tap the ⊞ (sliders) icon next to the event name to open the alarm editor. From there you can:
Tap Save to apply your changes. If you ever want to go back to the original timing, tap Reset to Default inside the editor.
Open the app and tap the Notifications tab. Each canonical hour has its own toggle. Switch any event on or off — the schedule updates automatically within a few seconds.
Ave Maria Clock schedules three days of notifications in advance and automatically extends the schedule so you always have upcoming alerts queued. A background refresh runs approximately once per hour to keep times accurate even when the app is closed. Stale notifications are pruned automatically — you will never accumulate outdated alerts in your notification centre.
The upcoming notifications schedule has moved to the About sheet for a cleaner layout. Tap the ⓘ button on the Clock tab, then tap Schedule under Explore to see all queued canonical hour notifications and their fire times.
At very high latitudes (near the Arctic or Antarctic), the sun may not rise or set at all on certain days. In those cases the solar calculations cannot produce a result and the app will show this message. Solar events will resume calculating normally when the sun returns to a standard rise/set pattern at your location.
Did the FAQ answer your question? Ave Maria Clock is free and always will be. If you find it useful, a small tip goes a long way toward keeping it updated.
♥ Leave a Tip — Thank YouAve Maria Clock does not collect or share your personal data. Your location is used only on-device to calculate solar times. It is never transmitted to any server, stored remotely, or shared with third parties. The app has no analytics, no advertising, and no account system.