The controls on World Clock change the comparison moment used by the Local Time card and every saved location card. They do not change the iPhone or iPad system clock, and they do not change the Sun and Moon calculations in a city’s Information screen.

Steps

  1. On World Clock, tap the Local Time card, its date, or its displayed time.
  2. In Select Date & Time, choose the date and time together.
  3. Tap Done.
  4. Compare the date and local time shown for every saved location.
  5. Drag the vertical 24-hour slider to move in 15-minute steps on the selected date. It snaps near whole hours and gives haptic feedback at whole-hour changes when supported.
  6. Use the light and dark portions of the slider as general daylight and nighttime context for your current location.
  7. Tap Now to return immediately to the current date and time.

Before you finish

  • The date and time controls update all saved cities together, which is useful for finding a meeting time.
  • The city Information sheet continues to show current city information; it does not use the main list’s selected historical or future date.
  • Future clock results rely on the time-zone rules available to iOS. Governments can change those rules.
  • The slider’s daylight divisions use location access when available. If location is unavailable, they are an approximation and should not be treated as the saved cities’ sunrise and sunset times.

Tips

  • For distant future planning, verify the time again closer to the event.
  • Note whether the target city is on the previous or next date.