Apple has just released iOS 11.3.1 to the general public. You can download the update by going to Settings > General > Software Update on your iOS device or through iTunes.
The update fixes an issue on some iPhone 8 devices with non-Apple replacement screens. Here’s more about the update from Apple:
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.
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.