Setting the date to 1 January 1970 will brick your iPhone, iPad or iPod touch

Date bug will prevent 64-bit iOS devices from booting up, rendering them inoperable even through fail-safe restore methods using iTunes

Manually setting the date of your iPhone or iPad to 1 January 1970, or tricking your friends into doing it, will cause it to get permanently stuck while trying to boot back up if it's switched off.

The bug within Apple's date and time settings within iOS causes such an issue that users are reporting that the fail-safe restore techniques using iTunes are not able to repair the problem.