Apple is working on a fix for the "1 January, 1970 bug" that recently caused iOS devices to crash. The fix is slated to be released in the next iOS update.
The date bug affected not just iPhones but other 64-bit Apple devices like iPad and iPod touch as well. It caused the devices to crash when the date was manually set to 1 January, 1970 or before. Devices set to this date went into a continuous reboot loop, essentially causing the device to be bricked.
Apple acknowledged the issue on 15 February and Apple support posted a brief update on its website titled "If you changed the date to May 1970 or earlier and can't restart your iPhone, iPad or iPod touch". The update said: "Manually changing the date to 1970 or earlier can prevent your iOS device from turning on after a restart. An upcoming software update will prevent this issue from affecting iOS devices. If you have this issue, contact Apple Support."
Although Apple has not specified the cause of the bug, popular YouTuber Tom Scott says that manually setting the date to 1 January, 1970 or earlier can also be interpreted at 00:00:00 in Unix time, the Wired reported. In iPhones, time is represented in integer, with the number of seconds displayed since 1970. Consequently, changing the time back to 1970 or before would cause the number value to become zero or go into a negative number, ultimately bricking the device.
Users already affected by the bug can attempt to fix their Apple devices themselves by either manually removing the battery or restoring through iTunes in DFU mode. However, since Apple will roll out a fix for the bug in its upcoming update, it may be prudent to wait.