Update 2017/10/31 - Apple has just released iOS 11.1. Check out the details here. While they don't specifically address Touch Failure with aftermarket screens, there could be some minor fixes which addresses issues that were not resolved with 11.0.3. Make sure to comment below if this update solves your problem.

This is a developing story so come back often to read new updates and stay up to date on this situation.
I will continue to research this issue and let this post serve
as a repository of updated information.

Is your iPhone 6S touch not working? It’s only been a few days since iOS 11 was released yet already there are more and more reports that upgrading your iPhone 6S to the latest iOS can cause your screen to lose Touch functionality. This mainly appears to be affecting the iPhone 6S but there are also reports of iPhone 7 series screens with the issue. (Update 2017/09/23 - I have also received notification from a few suppliers) The problem affects users that had their screens replaced with aftermarket (or “copy”) quality screens. This can be both DIY repairs as well as those done by independent repair shops.

Update 2017/09/24 - The problem appears to be caused by the software driver of the Touch Controller IC that is embedded into the display assembly. Aftermarket screens produced with Hancai or Tianma LCD's using the Aichungjia (a Flex/IC manufacturer) "copy" driver appear to be incompatible with iOS 11. This driver is said to be unable to handle the iOS configuration and therefore shutting down and causing the lack of Touch functionality. OEM or Original grade iPhone 6S and iPhone 7 series replacement screens are not affected by this problem. Thanks to Waqas Javed of MobileSentrix.com for sharing this information.

Touch Controller IC on an iPhone 6S

Touch Controller IC on an iPhone 6S

Update 2017/09/26 - Apple has just released an update to iOS 11. Version 11.0.1 is now available for download. However, Apple does not state what bug fixes were included in this release. It is possible that this will attempt to address the "Touch not working" issue as we have learned that Apple engineers were contacting independent repair shops to understand the nature of this problem.

Update 2017/09/27 - According to this report in Ars Technica, the latest update (v11.0.1) is only focussed on fixing a Microsoft Exchange Server bug. Independent repair technicians have also confirmed that this update does not address the Touch issue.

From the Apple website : iOS 11.0.1 includes bug fixes and improvements for your iPhone or iPad. For information on the security content of Apple software updates, please visit this website: https://support.apple.com/kb/HT201222

Update 2017/09/28 - According to AppleInsider, Apple has released initial public betas iOS 11.1. No official news on whether or not Touch issues will be addressed.

Update 2017/10/03 - Apple has just released iOS 11.0.2. It addresses bugs related to "crackling sound", photos and S/MIME attachments. There is no official indication that it will address the Touch issue. I have not seen or heard of any reports from the repair community, as of 3PM EDT, that would indicate that this release solves the Touch problem.

Update 2017/10/05 - Apple has stopped signing both iOS 10.3.3 and iOS 11.0.0. It is no longer possible to downgrade unless you had previously saved your SHSH2 Blob (see this article on GadgetHacks). 

Update 2017/10/9 - According to the website IPSW.ME, Apple is still signing the iOS 10.3.3 for the iPhone 6S. For those of you still having problems, I would highly encourage you to downgrade while you still can.

Update 2017/10/11 - Apple just released iOS version 11.0.3 and it claims to address the Touch Failure on aftermarket screens. For those of you that have been waiting for an official fix, it appears to be here. Make sure to comment below if this update solves your problem.

Update 2017/10/31 - Apple has just released iOS 11.1. Check out the details here. While they don't specifically address Touch Failure with aftermarket screens, there could be some minor fixes which addresses issues that were not resolved with 11.0.3. Make sure to comment below if this update solves your problem.

*On the iPhone 6S and up, the Touch Controller IC's have been combined and moved from the logic board (Cumulus/Meson) to the display assembly flex connector. The iPhone 6 Plus, in particular, suffered from Touch Disease due to the location of the Touch IC's on the logic board and the 'flexiness' of the housing.

So if you recently had your iPhone 6S / 6S Plus or iPhone 7 / 7 Plus screen replaced, there is a possibility that upgrading your phone to iOS 11 may cause the Touch functionality to fail. If you know for certain that you had an aftermarket screen installed then the risk is increased. Currently there is no real solution to this problem other than installing an OEM/Original grade screen (or a compatible aftermarket, speak with your repair shop or vendor for more details) or restoring your device to iOS 10.3.3. This is not straightforward, as iTunes will not do it by default. You can download a utility program like 3uTools (www.3u.com) that will allow you to do this or follow the instructions on this WikiHow webpage. However, you have to hurry because Apple only keeps previous versions of iOS properly signed and authorized for a few weeks following the release of a new version. After that, your phone will be locked onto iOS 11 and your only real recourse will be to either work with your repair shop/vendor or wait until public pressure forces Apple to patch iOS to accommodate these lower quality aftermarket screens.

What is an aftermarket screen? 
All iPhone screens are not created equal. While many customers seek the lowest price, the old adage of “you get what you pay for” also holds true for replacement screens. The stark reality is that only Apple can offer you a true, fully original replacement screen. Any screen you get from an independent repair shop, whether they’re a retail store from a large national chain or a small kiosk at the mall, or buying them yourself on eBay or Amazon for a DIY repair, is not going to be a fully original screen. There’s nothing wrong with that. Not everyone can afford a replacement screen from the Apple Store. Even those who wish to have it replaced by Apple can be turned away if their phone is too damaged. Then there are the millions of iPhone owners worldwide who don't even have access to an Apple Store. The third party ecosystem insures everyone can get his or her phone replaced at a price point that is acceptable to his or her reality. The problem lies in the fact that most people don’t know they are getting lower quality screens either because they weren’t told or because they didn’t understand the difference.

What kinds of screens are available at independent repair shops and popular online retailers?
It can be very confusing to determine exactly what you are buying because there are so many terms thrown around. I frequently look at repair shop websites, eBay & Amazon and it seems like everyone is selling “real”, “AAA”, “top quality”, “A+” screens. Yet when you look at their pricing, some repair shops charge less for the complete repair than what reputable wholesalers charge for selling just the screen alone. How can that be? It's not volume or special "connections". The reality is much simpler; those who offer bottom dollar prices are selling bottom quality screens. 

What kind of screens does Refectio offer?
Refectio always stocks the highest quality grade of screens available in the market. All of our replacement screens for current model phones, such as the iPhone 6, 6S and 7 series, are original-quality screens. For some older models, such as the iPhone 5/5C, only aftermarket screens are available but we still only source our screens from reputable suppliers who offer us extended warranties. They cost us more but this is what allows us to offer you the best warranty.