My iPhone screen isn't working! The screen is stuck! What's happened, and how can I fix an unresponsive iPhone screen?

After installing iOS 9 some users found their iPhone suddenly had a stuck screen that - no matter how hard you try - won't respond to your increasingly fervoured finger tapping. The iPhone is unusable, and, worse, you can't even turn it off or restart as the swipe doesn't work. See also: How to install iOS 9 tips.

If you want to know how to fix an unresponsive iOS 9 iPhone screen problem, rest assured: most of the time it's quite easy. We'll start off with a simple fix that should solve most of the problems, although some people have found they need to perform it several times.

But more recently a bigger related iPhone screen issue has been getting some media attention, and if this is what's causing the problem you may have more to worry about. We'll look at that problem - which has become known as 'Touch Disease' - in more depth, including how to avoid it and what to do if you experience it, later in the article.

Note that this article is about unresponsive and stuck iPhone screens - screens that simply don't respond to a toucn or swipe. For screens that are visibly broken, cracked or shattered, read How to repair a cracked iPhone or iPad screen.

iPhone screen not working: Simple fix for unresponsive iPhone screens

To get your iPhone screen working again simply hold down the circular Home button and the On/Off (Sleep/Wake) button at the same time for around 10 seconds.

This will restart the broken iPhone, and should restore the screen to full working order.

Clearly we await a better Apple software fix, but in the meantime this should work.

Read next: From Antennagate to Yellowgate: The 10 biggest Apple scandals

Touch Disease: What is it, how do you know if you've got it, and what to do if you get it

The iPhone 6 and 6 Plus models were launched back in September 2014 and, on the brink of the iPhone 7's arrival, a whole new scandal has hit the headlines: Touch Disease.

The popular repair site iFixIt is responsible for identifying Touch Disease (and naming it too), although they say the issue has been around for the two years since launch. Touch Disease is very likely an additional symptom of Bendgate - a design flaw with the iPhone 6 range of devices that meant the devices could become bent.

Touch Disease: What is it?

Phones affected display a small flickering grey bar at the top of the screen - about the height of the iOS menu bar. It looks a bit like old-school TV static. Additionally - or alternatively - the screen may become completely unresponsive to touch.

The problem can be intermittent, with some users saying that it appears when they first wake their devices but then goes away after a minute or so. Some users say that applying pressure to the top screen area can fix the issue, while others say that twisting the device slightly is also a temporary fix.

Here at Macworld UK we DO NOT recommend you try either of these techniques because you could make the problem worse or break the phone entirely.

Touch Disease: Which phones are affected?

The iPhone 6 and iPhone 6 Plus are the only models affected by Touch Disease.

The successors to these models, the iPhone 6S and 6S Plus, are not affected because Apple redesigned the logic board, moving the affected components (see below), and also making the devices more structurally rigid so that they're far less prone to bending.

Older phones are also not affected. The iPhone SE, launched in March 2016, is not affected because it's based significantly on the older iPhone 5S design.

It's not known if the forthcoming iPhone 7 and 7 Plus will be affected but it's very unlikely considering they'll probably be a design evolution of the 6S and 6S Plus.

An individual writing on Reddit, and who claims to be an Apple technician, said he was told by managers that the issue was fixed in models manufactured after November 2015 - although he's found phones manufactured after this date are still affected. Sites like iPhone IMEI can provide details of when a phone was manufactured, even if they're not always 100% accurate.

Touch Disease: What causes it - and how to I avoid it?

iFixIt spoke to various independent iPhone repair shops and came to the conclusion that the Touch IC chips on the phones' logic board break away partially, making for intermittent electrical connections. This in turn causes the above-mentioned symptoms.

In later models of iPhone the Touch IC chips are moved onto the display assembly, which is why the 6S and 6S Plus are not affected. In older phones the chips were protected via a metal shield, so again aren't affected.

Experts say the Touch IC chips break away from the board during everyday use, such as when a phone flexes slightly when stored in a trouser pocket.

This is why applying pressure to the screen, or twisting it slightly, can appear to fix the problem - it forces the Touch IC chips to re-establish full contact with the logic board. However, this is not a permanent solution and the problem will return.

Notably, Touch Disease is not an issue with the screen or its digitiser (that is, the layer beneath the screen that registers touch), and replacing the screen will not solve the issue.

Because of its larger size, the iPhone 6 Plus is said to be particularly prone to Touch Disease - and iFixIt quotes one repair expert who reckons that virtually all iPhone 6 Plus phones will be affected at some point. However, for the sake of balance we have to point out that there are literally hundreds of thousands of iPhone 6 and 6 Plus users worldwide who have never experienced the issue.

Because it's not entirely clear what causes the Touch IC chips to detach, it's also not clear how to avoid it happening. However, a tough, rigid case might be a good investment and avoiding putting the phone in a trouser pocket might also be a good idea - especially if you like to wear skinny jeans!

Touch Disease: What do I do if you're affected

If your device is still within its guarantee period then take it to Apple, where they'll almost certainly either swap the logic board for a replacement, or swap the entire phone for a replacement.

At the present time Apple is not publicly acknowledging there's an issue, so will probably charge for a repair if your device is out of its guarantee period. Apple charges £236.44 for an out-of-warranty repair for the iPhone 6, and £256.44 for the iPhone 6 Plus. These prices drop to £59 and £79 if you're covered by AppleCare+.

In theory, the Consumer Rights Act here in the UK provides for getting a free repair or replacement within a reasonable time outside the guarantee period but - as Which? Magazine reports - it's a grey area and you'll probably have to argue the case.

Third-party repair shops are able to resolder the Touch IC chips to make a permanent connection, and some also apply a metal plate over the chips to stop the issue recurring. The cost is likely to be a fraction of what Apple charges. However, a third-party repair is likely to make your phone invalid for any official product recall in future, or any other repair for which you might want to approach Apple. Additionally, it can be hard vouching for the quality of third-party repairers - one individual on Reddit reported that he had Touch Disease fixed by a third-party repair shop, but they broke the phone's GPS chip and camera while doing so.

For these reasons, we always advise taking your phone to Apple first and foremost if there's any kind of issue. With the pressure building in media reports of Touch Disease, there's a possibility Apple will eventually acknowledge this issue, in which case they'll create a repair programme that will be free of charge.

A low-fi solution reported by one Redditor is to put a coin between the back of the iPhone, just beneath the camera lens, and its case - although the case has to be of the rigid and hard variety, and not soft or floppy. This trick applies a small amount of pressure that forces the Touch IC chips to connect.

Touch Disease: What is Apple saying?

Right now, Apple isn't saying anything and, as mentioned, has not acknowledged that there's an issue. Macworld UK has approached Apple for comment.

Several people discussing the issue on Reddit claim to be Apple technicians and say that the problem has been known for a long time - to the extent where one Apple Store saw several customers a day showing up with the issue. However, perhaps because the problem has now been fixed via improved manufacturing, hardly any devices show the issue at the present time.

Additional reporting by Simon Jary

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