Your iPhone can help save your eyesight

The iPhone 14 is a great phone full of wonders, and that can be a problem- too much screen time, or too much time close-up to your phone can be bad for your eyes. That can mean eye strain for adults - tired eyes, blurred vision or even headaches. And in children, it can increase the likelihood of myopia, also known as near-sightedness or short-sightedness.

Apple already offers a selection of Screen Time features for iPhones, iPads and Macs, but with iOS 17 it's adding one specifically designed to save your eyesight. It's called Screen Distance and while it's optional – you have to turn it on in Settings > Screen Time – it sounds like it could be something you'll want to switch on. 

There's one caveat - your iPhone or iPad needs to have Face ID. That's because Screen Distance uses the same sensors, which Apple calls TrueDepth, to decide if you're too close.

How can an iPhone help your eyesight?

A lot of the "don't sit too close to the TV" stuff we've all heard is an urban myth, and based on one of my favourite bits of useless information.

In the US during the late 1960s, a batch of defective TVs turned out to be emitting potentially dangerous amounts of radiation, and owners were warned to ensure kids sit six feet away from the TV. Those dangerous displays aside, the reality is that sitting too close to a TV doesn't make you short-sighted; it's more likely to be a sign that you are short-sighted.

But phones are a different proposition. That's because we hold them much closer than we've ever been to a TV, and we have them there for longer. Much longer.

A 2018 study by Nielsen reported that, on average, we spent well over three hours every day with our phones clamped to our faces. That can definitely lead to eye strain, to dry eyes (which are a menace for me personally) and there are concerns that in the longer term it may actually cause our eyes to deteriorate slightly. 

Apple's solution is simple. It measures how close your iPhone or iPad is to your face and warns you if you're holding it too close for too long. It'll interrupt what you're doing with an "iPhone is too close" message and urge you to move it to arm's length.

It's interesting that Apple has announced Screen Distance while it's been finishing off Vision Pro, because of course that's designed to be glued to your face for long periods too.

I'm getting plenty of press releases from optical firms suggesting that it'll be a vision-damager. It all seems pretty anecdotal to me and some of the claims definitely veer into junk science territory, but as someone whose eyes are dryer than the Sahara due to my 24/7 screen habit, it'll be interesting to see whether any vision issues emerge when (or if) headset use becomes something we all do for long periods.