iPhone can be completely broken by changing the date because of iOS bug

Changing the phone’s date to 1 January, 1970 — and there doesn’t seem to be any dependable solution, short of heading to an Apple Store

Changing an iPhone’s date could lead it to completely shut down, according to reports.

A bug in the operating system means that the phones will break if their date is changed to 1 January 1970, and they are rebooted.

Unlike other bugs, this doesn’t appear to be recovered from. Users have been strongly advised from testing it out, or from doing it to others, because it could cause permanent problems for the phone.

Some people have reported that the phones are revived again after five hours. Others have said that the problem can be overcome by swapping Sim cards around.

But the most straightforward way of getting the problem fixed is to contact Apple Support, or to go to the Genius Bar at an Apple Store.

A number of reasons for the problem have been proposed for the issue. The most convincing appears to be that setting the phone to that time makes the clock less than zero, which it can’t deal with and so breaks down.

Time on many computer systems is set with reference to 1 January, 1970, which is known as the “epoch” — phones and other devices count away from that time and express the date by working out how long has passed since. That system has led to other issues, such as the Year 2038 problem, when phones could start breaking down because it is too long since 1970.

The 1970 bug is the latest in a run of odd issues that have caused iPhones to crash. Those have included an iMessage that broke phones, a website that brought them to a standstill, and a brief moment where Safari on all phones would cause them to break down.

The problem appears to be limited to iPhones since the 5s, and iPads of a similar age, that have iOS 8 or later installed.