The Glitch That's Bedeviling iPhone Alarms

Duncan Madden, a copywriter in London, says his iPhone cost him £80 ($129) last week. Thanks to a software glitch, his phone—which he also uses as an alarm clock—roused him from bed an hour later than he set it for on Nov. 1 and 2. "It's made me late for work two days in a row," says Madden, 34. "I'm freelance, and I charge an hourly rate, so it's obviously cost me a reasonable amount of money."

Y2K this is not. There are no worries that planes will fall from the sky. Yet when Europeans turned their clocks back during the wee hours of Nov. 1 in accordance with the end of Daylight Savings Time, iPhones hiccuped. The phone's primary clock, which is synced with a server somewhere in the cloud, recorded the time change just fine. So-called recurrent alarms, those set by users to sound at the same time on given days, did not. Those who relied on their phones to wake them at, say, 6:45 every weekday ended up snoozing until 7:45.

Disgruntled dozers responded by—what else?—complaining on blogs, message forums, and social media sites such as Twitter. "Apple's (AAPL) new iPhone 5 will be able to do payments," wrote one Twitter user, referencing a rumor about the company's next-generation smartphone. "Seeing as they can't do alarm clocks, this worries me."

The software bug has its roots in the U.S. Congress. In 2005 legislators amended the Uniform Time Act to extend Daylight Savings Time, starting in 2007. The change, intended to prolong the number of daylight hours and thus conserve energy, means Americans move their clocks back a week later than Europeans do. The recurrent alarm feature in the latest iPhone software didn't account for the discrepancy.

After Nov. 7, when the U.S. ends its prolonged Daylight Savings Time, the clocks of the DST-observing world will be in sync again, and the problem should be moot. Until March, that is, when DST begins again. Natalie Harrison, an Apple spokeswoman, says the company is aware of the issue. The problem first popped up in Australia and New Zealand, which change their clocks weeks ahead of Europe. (It's spring there, and clocks are moving in the other direction, so iPhone users woke up an hour early, not late.) The company says it will deliver a fix along with a scheduled software update later this month. In the meantime, "We suggest customers set non-repeating alarms for now," says Harrison.

Or not. Simon Johnson, a 42-year-old Web interface designer who works in the same office as Madden, was also affected by the iPhone glitch. "To tell you the truth, it was rather good to get to work late," he says. "The Tube was empty."

The bottom line: A software glitch related to Daylight Savings Time caused some iPhone owners in Europe to oversleep.

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