This iOS date change trick can brick your iPhone forever.

A new bug has been discovered in iOS devices, which kills your phone for sure. This bug is related to date setting of your phone.
As per the video shared by an Youtube user Zach, if your set your iOS device’s date to 1st Jan, 1970, your device will be permanently bricked.
In order to change your phone’s date and time settings, you need to go to the Settings App and tap the General Menu, choose Date & Time and turn off the Set Automatically oprion. And then change your date by scrolling backwards till you reach 1970. Once you have reached 1970 year, change the date to 1st Jan. Now, the phone will work file, but if you perform a restart with this date been set, your device will not come back ON. You can put in into DFU and even try connecting it to iTunes to recognize and perform a restore, still the device will be stuck at the bootup screen. The Below is the shared video, which illustrates the bug issue in practice. But we’ll recommend not to try this with your or anyone’s phone.

This bug affects any iOS device that uses a 64-bit processor and is running iOS 8 or newer, which includes iPhones, iPads and iPods. If you are unsure, 64 bit processors are the A7, A8, A8X, A9, and A9X (iPhone 5s or later, for instance). But if you are having a 32bit processor device, then you are safe.

There are few possible causes of the issue, but according to Tom Scott, an Youtube video maker and developer, changing the date close to January 1, 1970, which is 0 in Unix time, may be resulting in an integer underflow — in this case, a date prior to January 1, 1970.