Want to go back in time to Jan. 1, 1970? Just make sure you don't do it on your iPhone.
Changing the Date & Time settings to that fateful date will disable your device, Apple users report. And good luck trying to get it to restart: Connecting the disabled phone to your computer and trying to reboot it via iTunes won't work.
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One chagrined user posted about his device's demise on an online Apple help forum:
"Hello, I was playing around with my Date & Time settings and I changed the time to January 1st 1970. I shutdown my phone and restarted it, the result is a bricked iPhone. I've tried restoring, updating, but nothing seems to be working."
Tech website 9to5mac posted a video demonstrating the date bug, which appears to only affect Apple devices with 64-bit processors — meaning iPhone 5S, iPad Air, iPad Mini 2 and the sixth-generation iPod Touch, or newer models of those devices. Trying to restart the device seems to only bring back the Apple logo screen, where it apparently gets permanently stuck.
Apple hasn't responded to a query from NBC News about the apparent bug.
What's so special about 1 January 1970? Techie commenters on Reddit and elsewhere note that's the start of Unix time, a way for developers to track time as a running total of seconds. Manually setting your Apple gadget to that date apparently causes a conflict that will choke the device.