The iPhone Clock app has a quirk that few people know about

The iPhone Clock app has been around since the original iPhone launched 19 years ago, and for the most part it’s still a pretty simple default app. However, there’s a little curiosity hidden in the alarm settings that went viral in mid-2025, as well as another quirk that we’ll talk about below. To put it simply, the alarm clock’s scrolling hours and minutes seem endless at first glance, but rapidly scrolling the hours and minutes will eventually reach a dead end at 4:39. For those who prefer military time, it ends at 4:39 p.m. Go ahead, try it and see for yourself.

Open the Clock app, select Alarms, press the + button and start scrolling through the hours and minutes until the end. It will take several swipes, but not too many if you scroll as fast as possible, which is why most people never noticed it in the first place. However, this small final point does not mean that you are limited in setting up alarms.

So why does iPhone alarm stop at 4:39am? The specific hour and minutes seem a bit strange and random, don’t they? Well, Apple hasn’t weighed in on this, but reports and discussions online offer different explanations, such as something called Tableview that user X thinks is involved. For the most part, just treat it as an interesting quirk. The numbers don’t add up to 23 or anything, so there’s no need to delve into conspiracy theories.

Who knew? But seriously, there’s another little detail here that’s easier to spot once you know where to look. The Clock app icon is not static. It tells you the current time, including a moving second hand. Apple introduced this feature in iOS 7, back when we were still grunting and finger painting on cave walls. If you’ve always opened the app to check the time, you’ve never really had to.

Additionally, an even more subtle feature is discussed in the opening paragraph. Normally, the second hand moves in a continuous “sweep” motion all around. However, on iOS 26.1 and later devices, Low Power Mode changes the movement to a tick once per second, like a traditional quartz clock. The time is still shown, of course, but with less fluid animation. This is only a visual change, and no audible ticking is involved.

If you’re looking for an extra option hidden in plain sight, open Stopwatch in the iPhone Clock app and swipe across the screen. You can switch between digital and analog stopwatch faces without installing another app. Unlike the alarm endpoint, this is a documented feature included in the iPhone user guide.

Now that Clock’s dirty laundry is exposed, how about changing the appearance of the app? The worst and best iPhones offer a few clock display options, although they fall far short of the aesthetic variety offered by other apps.

If you want a large bedside alarm clock, connect your iPhone to a charger and stand it upright on its side. This puts it in StandBy mode, which displays widgets, photos, or just a good old-fashioned clock. Change the types of clocks displayed by swiping left or right.

Finally, you can enable night mode so that sleep mode adapts to the dimly lit environment of a typical bedroom when it’s time to sleep. The screen will display an intense red tint, so it’s a little less intrusive, especially if the nightstand is at your face level. It’s not a mysterious quirk or anything, but it exists.

However, if you expect your iPhone to behave exactly like a standard bedside clock, you’ll need to make sure Always On Display is enabled in Settings. It’s best to place a MagSafe charger with a kickstand on the back. Some older iPhones don’t have an always-on display, so you’ll have to give the screen a little nudge to turn it on or you might pester Siri about it.