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Apple Releases iOS 11.3.1 Update With Fix for Third-Party Display Repair Issue
The iOS 11.3.1 update can be downloaded for free on all eligible devices over-the-air in the Settings app. To access the update, go to Settings --> General --> Software Update.
iOS 11.3.1 introduces performance improvements and bug fixes for issues that have been discovered since the launch of iOS 11.3. The update includes a fix for a bug that caused third-party repairs done on iPhone 8 models using aftermarket parts to disable the touch functionality of the screen. From Apple's release notes:
iOS 11.3.1 improves the security of your iPhone or iPad and addresses an issue where touch input was unresponsive on some iPhone 8 devices because they were serviced with non-genuine replacement displays.The iPhone 8 and iPhone 8 Plus repair issue was discovered following the release of iOS 11.3. After updating, some iPhone users that had sought display repairs from non-Apple service providers saw the touch screen functionality of their devices disabled, resulting in serious headaches for repair shops.
Note: Non-genuine replacement displays may have compromised visual quality and may fail to work correctly. Apple-certified screen repairs are performed by trusted experts who use genuine Apple parts. See support.apple.com for more information.
At issue was a small microchip in the display, which disabled touch functionality after the update. At the time, it was not clear if the non-functional displays were a bug or a deliberate move by Apple, but it appears it was a bug. While Apple is fixing the display problem via the iOS 11.3.1 update, the company's release notes encourage customers to seek out authorized providers and genuine parts.