Apple has announced a logic board replacement program for some iPhone 8 units. The affected devices, which have a manufacturing defect, were sold in Australia, China, Hong Kong, India, Japan, Macau, New Zealand, and the United States between September 2017 and March 2018. Note that this manufacturing defect affects only the iPhone 8 and not the iPhone 8 Plus or any other iPhone model.
Symptoms of the problem include unexpected restarts, freezing screens, and phones that won’t turn on. If your iPhone 8 has an eligible serial number, which you can check on the replacement program page, Apple will replace its logic board for free. To find your iPhone’s serial number, go to Settings > General > About and scroll down to Serial Number. Press and hold the serial number to display a Copy button; tap it to copy the number for pasting into the replacement program’s page. If everything is set up correctly, the data should also transfer to your Mac’s clipboard via Universal Clipboard for pasting there too.
If your iPhone 8 is eligible for the replacement program, you have thee options: finding an Apple Authorized Service Provider, making an appointment at an Apple Retail Store, or contacting Apple Support to arrange mail-in service. The first two will probably offer the fastest turnaround time, assuming either is within a reasonable driving distance.
As always, back up your device before handing it over to Apple, because the technician may need to erase it for some reason. I like to back up and then erase my devices before I send them in. That way I don’t have to give my passcode to Apple, and there’s no chance that a technician will see any of my personal information.