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Introduction

Apple officially launched iOS 11 on Tuesday the 19th of September, and it is already causing issues for users. We’ve personally had experience with a number of customers coming in and reporting problems with the touch sensing on their iPhones after upgrading. Often the screen becomes non-reponsive, glitches or is just generally unusable- something which can be very frustrating for the users.

The common factor in all those cases appeared to be that these people had had their screens replaced at some point.

After considerable testing, we’ve narrowed this issue down to aftermarket (or “copy”) LCDs. As we discussed in a previous article on our “Disc Depot Dundee” website copy LCDs are manufactured very differently to the Apple ones. There are only a handful of factories producing the core LCD themselves, all of them based in China. These factories- for example, Jing Dong Fang (BOE)- already produce LCDs for laptops and televisions and cannot produce a complete iPhone LCD due to the risk of getting into trouble from Apple or the Chinese government. As a result, they’ll provide the core LCD to another company who add further parts to the base LCD to form a complete unit. It’s the rest of these parts that cause the variance in quality from screen to screen. For instance, there are over a hundred companies manufacturing the digitizer driver IC, which is the main component responsible for touchscreen functionality.

How Aftermarket Digitizer ICs Cause Problems

Early Days- Reusing Genuine Apple ICs

In most copy LCDs the digitizer driver IC isn’t strong enough, and this the main reason for lagging or non-responsive touch. This wasn’t always the case. With very early copy LCDs, the Chinese manufacturers salvaged and reused digitizer driver ICs from broken original Apple screens. In effect, they were producing a hybrid that included some parts from a genuine (but broken) Apple LCD. This added to the cost of the copy LCDs, especially as there were still only limited numbers of broken Apple LCDs.

Compatible Copies Developed… and Cause Problems

This use of genuine digitizer driver ICs also encouraged the dramatic rise in stores that used copy LCDs. Although their visual quality didn’t match that of the original Retina display, the fact that the touch functioned exactly as it should- since it contained original parts- gave them false confidence that copy iPhone screens were okay to use.

All this drove up demand and increased competition for the limited supply of original ICs. This forced manufacturers to develop their own “stable” versions of the digitizer driver ICs, and it’s these that are almost exclusively used today.

Unfortunately, these (supposedly) compatible replacement ICs are the source of most of the touch issues with copy iPhone LCDs. The IC is simply not powerful enough to drive the touch correctly. This results in slow response to touch, jumping or jittering when you’re dragging an icon on the screen, having to press the screen more than once to respond, or- as some iOS 11 users are now reporting- where the touch doesn’t work at all.

Identifying Which Copy Screens Have This Problem

It should be noted that not every copy screen seems to have this issue. In addition, because there’s only limited information available on the different manufacturers of each component- and since most repair stores who fit these screens have no idea who assembles the final LCD/digitizer unit anyway- it is difficult to narrow it down to one particular combination.

What we do know, so far, is that Hancai and Tianma LCDs that use a copy digitizer driver IC made by Aichuangjia are having issues. The IC isn’t strong enough to handle the iOS 11 configuration and this will cause the IC to shut down and have no touch. This LCD and IC combination is usually found on the lower end screens as it costs more to produce a better flex and IC.

The Solution- Use Genuine Original Replacement Screens Whenever Possible

If you are experiencing touch issues with your iPhone we highly recommend getting the screen replaced with an original LCD. We’ve always encouraged customers to go for original screens in the first place since- although they may cost slightly more than a copy LCD- they deliver far higher and more consistent quality. As we’ve now seen, this will also save you money in the long run too!