Some Apple Watch Series 4 owners in Australia experienced crashes and reboots on Saturday due to a bug that surfaced because of the daylight saving time change (via 9to5Mac).

applewatchseries4aluminummodels
According to Reddit users hit by the Apple Watch bug, the root of the problem appears to be the Infograph Modular face's Activity complication, which displays a timeline graph with hourly data for the user's Move calories, Exercise minutes, and Stand hours.

When daylight saving time (DST) lops an hour off the typical 24-hour day, the Activity complication is apparently unable to compute the change and draw the timeline graph with only 23 hours, which throws the Apple Watch into an endless reboot loop until the battery runs out.

According to reports, the bug corrected itself when the date rolled over the next day and the normal 24-hour day was reinstated, but some users were able to restore normal function to their watch before then by removing the Infograph Modular watch face via the iOS Watch app.

This isn't the first time Apple has been caught out by daylight saving time changes, but the company has a few weeks yet to fix this latest DST bug before it happens again when Europe and the U.S. change their clocks on October 28 and November 4, respectively.

Related Roundup: Apple Watch Series 6
Buyer's Guide: Apple Watch (Neutral)

Top Rated Comments

Reason077 Avatar
33 months ago
Seems a little ironic that a Watch, of all things, can’t handle the DST change correctly.
Score: 23 Votes (Like | Disagree)
coolfactor Avatar
33 months ago
Seems a little ironic that a Watch, of all things, can’t handle the DST change correctly.
Dealing with timezones and human-made exceptions to normal time cycles, such as Daylight Savings Time, is complex stuff! Even harder to test! I give Apple full credits for doing their best with this. But I am surprised it hasn't been fixed in some low-level library shared across all of their platforms.
Score: 6 Votes (Like | Disagree)
chrono1081 Avatar
33 months ago
Dealing with timezones and human-made exceptions to normal time cycles, such as Daylight Savings Time, is complex stuff! Even harder to test! I give Apple full credits for doing their best with this.
Bingo. People have no clue how complex date and time programming is. I dread every time I have to do it.
Score: 4 Votes (Like | Disagree)
allenvanhellen Avatar
33 months ago
I’m getting tired of Apple rushing stuff and leaving things undone. They may be small issues, but they’re growing in number.
Score: 3 Votes (Like | Disagree)
newellj Avatar
33 months ago
Correction: the changeover happens on early Sunday morning, not Saturday, but this is still Saturday in the US, ‘cause we live in the future!

Don’t you love time zones?
Totally, even within a time zone, going to the other side, or other end, of the time zone can be interesting. Changing days is arbitrary and a little bit of a mind-bender. Needless to say, those of us in NA appreciate those of you Antipodes serving as beta testers. :eek: :D. (meant in good will and good humor)
Score: 2 Votes (Like | Disagree)
Nozuka Avatar
33 months ago
I don't see a problem that they forgot about the time change on the complication. Can happen to the best of us.

But i'm a bit disappointed, that this complication bug reboots the whole watch. it should just kill the complication.
Score: 2 Votes (Like | Disagree)

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