I use my phone for almost eight hours per day, according to my iPhone—yikes. My eyes may feel uneasy at times, as if I have something in them, since I probably hold my iPhone near to my face a lot, particularly at night. Fortunately, Screen Distance is a secret iPhone function that may help myself and others take better care of our eyes.

See also: The Importance of Screen Time for Eye Health

Similar to a parent telling you to sit farther back from the TV or computer screen, the function alerts you when you’re holding your iPhone or iPad too near to your face. Cedars-Sinai, a health care company, states that although using a screen close to your face may not be harmful to your eyes, it may cause stress and irritation. Fortunately, this iPhone function attempts to lessen eye strain. Apple claims that it may even reduce the chance of nearsightedness, or myopia.

Here’s how to activate Screen Distance so you may rest your eyes.

Activate Screen Distance

1. Go to Settings.
2. Select “Screen Time.”
3. Select “Screen Distance.”

Two screenshots next to each other. The screens say “Screen Distance” on the left and “How Screen Distance Works” on the right.
When you initially visit Screen Distance, these displays show up.
Zach McAuliffe/CNET screenshot
After that, you’ll see two displays that describe Screen Distance and its operation. After selecting “Continue” on both screens, Screen Distance will start up automatically. Only the first time you enter Screen Distance do both screens show.

Now, after a few minutes of holding your iPhone too near to your face, a notice that reads, “iPhone May Be Too Close,” blocks your screen.

Two screenshots next to each other. iPhone May Be Too Close is shown on the left side of the screen, while a checkmark is displayed on the right side. Distance from the Screen
Screen Distance disables your iPhone’s screen when you hold it too near to your face over an extended period of time.
CNET/Zach McAuliffe
Up till you hold your iPhone further away, your screen stays obscured. After that, a checkmark appears on your screen; to remove the block, you must hit Continue.

See also: How Optometrists Suggest Overcoming Eye Strain

Disabling Screen Distance
One helpful iOS feature that may lessen eyestrain and potentially lower the risk of nearsightedness is Screen Distance. Here’s how to disable Screen Distance, however, if you find the alerts more bothersome than useful.

1. Go to Settings.
2. Select “Screen Time.”
3. Select “Screen Distance.”
4. Next to Screen Distance, tap the toggle.

Without being distracted by your phone or your parents, you may now resume holding your iPhone as near to your face as you want.