Apple CEO Tim Cook holds a new iPhone 14 Pro during an Apple special event in Cupertino, California, Sept. 7, 2022.

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Apple’s iOS 17 will include one of the biggest revamps to the iPhone’s phone app in years.

The newly updated Phone app included with the software update adds real-time voicemail transcriptions, “contact posters” so users can choose the photo that shows up when they dial another person’s iPhone and an updated user interface with a bolder font.

But one tweak will require longtime iPhone users to retrain their muscle memory. In beta versions of iOS 17, Apple has moved the “End Call” button. It’s now moved to the lower right-hand corner, instead of centered in the bottom third of the screen.

Where the red button is on iOS 16 lands between two buttons in iOS 17: one that turns the call into a FaceTime call and another button that brings up the iPhone’s dial pad.

It’s easy to imagine someone with muscle memory from years of hanging up phone calls accidentally pressing where the button used to be. Some people have already said on social media that it might take a while to retrain themselves to the new button location.

Most people don’t have iOS 17 yet. It’s only available in beta form and is meant for people who don’t mind helping Apple catch bugs. It’ll be released to the public and everyone’s iPhone in the fall, shortly after new iPhone models are announced.

It’s not the first time Apple has rearranged a years-old user interface to put key buttons closer to the bottom of the phone, where it’s more ergonomic, especially as phone screens get larger.

In 2021, Apple changed its Safari browser in a beta version of iOS 15 to put the URL bar at the bottom and updated its design. However, by the time the final version was released in September, Apple had tweaked the design, rolled back some changes and gave users an option to put the URL bar back on top of the page.

An Apple representative didn’t respond to a question about whether the new call screen might change back or become customizable.

Here’s what the new call screen looks like on a beta version of iOS 17:

CNBC/Screenshot

Here’s what it looks like now, on iOS 16:

Screenshot/CNBC