What the iPhone’s built-in world clock can’t do
It answers the first question well and the other two not at all — an honest look at where Apple’s Clock app stops.
The Clock app that ships with every iPhone has a World Clock tab, and for the basic job it is fine. It is worth being precise about where it stops, because "there's one built in" is a reasonable thing to think.
What it does well
- A list of cities with their current local times.
- Today/tomorrow/yesterday indication relative to you.
- A light/dark indicator for whether it is day or night there.
- Reliable, free, already installed, and correct — it uses the same underlying time zone database as everything else on the device.
If your only question is "what time is it there right now," it answers it, and there is no reason to reach for anything else.
Where it stops
No conversion. There is no way to ask "if I pick 3pm on Thursday, what time is that for them?" The World Clock shows the present and only the present. In practice this is the question people have most often, and it is the one that requires the most care because of date rollovers and daylight saving.
No overlap. Nothing tells you when two cities are both awake. You can read two numbers and work it out, but the app will not compute the shared window, and that computation is fiddly precisely where it matters — half-hour zones, and gaps that move twice a year.
No map. No visual sense of where daylight currently is. This sounds decorative and is not: a day/night map answers "who is awake" for six places at once, faster than reading six rows.
Limited widget surface. The built-in Clock widgets are constrained in what they can show, and the world clock is not the part Apple has invested in.
No search by alias. You search by city name. If you think of a place by its local name or by its zone rather than its English city name, you have to know the city.
Where the gap actually shows up
Not in "what time is it in Tokyo," which the Clock app handles.
It shows up in: scheduling a call three weeks out that crosses a daylight-saving transition; working out whether a deadline lands on the same date at both ends; finding the one usable hour with someone eight zones away; and glancing at a Home Screen to see who is in daylight without opening anything.
Those are the three questions — now, then, and overlap — and the built-in app answers the first.
Being fair to it
The Clock app is not trying to be a scheduling tool. It is a clock, an alarm, a stopwatch and a timer, and the world clock is a small tab inside it. Judged as what it is, it is well made.
The question is only whether the first of the three questions is the one you actually have. For a lot of people it is, and this page ends with them keeping the app they already have.
Related: World clock · A world clock widget for iPhone
Timezone: World Clock Widget
A world clock, converter and live day/night map for iPhone — 325 cities, offline, no account.
Figures on this page are computed from the IANA time zone database. Last generated 2026-08-18.