Apple released iOS 11.3.1. It states that the tech giant has found a solution to a problem where users have replaced their displays with third-party repair services (19659004) According to the Release Notes, "iOS 11.3.1 improves the security of your iPhone or iPad and fixes a problem Touchdown on some iPhone 8 devices did not happen because they were serviced with a non-original replacement device "The versions of this edition seem to have been circulating for some time – 2017 has an iOS update for some iPhone 7 users The touchscreen functionality is temporarily disabled, and earlier this year, iOS 11.3 did the same thing with iPhone 8 models.  Both retailers and customers suspected that Apple could purposely fail to enforce the problem and other malfunctions caused by the replacement of other components.
"It's very easy to go into the rabbit hole, thinking that Apple is trying to make it so uncomfortable enough to consider even third-party repair a reliable option," wrote RepairMapr founder Kev Notton to the motherboard. "This scares me because they're the manufacturer, and they finally hold all the cards in their hands."
It's possible that some users were actually forced to put a fair share of the bill in Apple's official repairs. In that case, they might justifiably be angry that this could be a problem with an update being resolved. iOS 11 was notoriously buggy after its release, and Apple has worked so hard to fix bugs that this year's iOS 12 update is said to have fewer new features.
Although Apple says the 11.3.1 fix will work, it also alerts people who do not use third-party repair shops:
Note: Non-faithful replacement displays may have degraded image quality and may not function properly. Apple certified screen repairs are performed by trusted experts using genuine Apple parts. For more information, visit support.apple.com
Apple only admitted to its policy that third-party repair of a device would invalidate a device's warranty in 2017, but only if the warranty does not cover repair of the device Related to the screen. This month, the FTC warned six large companies that sell "automobiles, mobile devices and video game systems" where third-party warranty restrictions are illegal:
Despite receiving such warnings, most of the restrictive guidelines issued by Producers are not enforceable. The Magnuson-Moss Warranty Act of 1975 prohibits manufacturers from providing repair restrictions on any device that is warranted. According to the FTC, unless the manufacturer provides the parts or services to the consumer for free or receives a disclaimer, the customer can not require that certain repair requirements be met or the warranty void.
Soldering caused iPhone 6 and 6 Plus phones to lose touchscreen functionality. Apple finally stated the problem that phones were "repeatedly dropped on a hard surface" and "exposed to further stress". Customers could pay $ 150 to repair the equipment.
Other changes in the update 11.3.1 Addressing security vulnerabilities that allowed applications to obtain "elevated privileges" and the ability to "process maliciously crafted text messages for UI spoofing" (Ars Technica)  [9to5Mac]