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The killer feature that could make the iPhone 12 feel much,

The new iPhone 12 is probably going to have the expected upgrades: a faster processor, the latest iOS software, 5G wireless connectivity and a host of other updates that should make the iPhone 12 the fastest smartphone Apple ever produced.

But more than any other new bell or whistle, one new feature could make the iPhone 12 feel significantly zippier: A high-refresh-rate screen.
OK, we're entering Reddit rabbit-hole rumor territory here, but if it pans out, Apple (AAPL) fans will be thrilled. One rumor that has persisted this year is a 120 Hz display. That's a screen that can display 120 different frames, or images, per second.
The iPhone's current screen, like most smartphone and computer displays, is stuck at 60 Hz, or 60 frames per second. That doesn't feel slow, because that's what we're used to. But get your hands on a 120 Hz display, and you'll wonder how you ever survived with a measly 60 frames per second.
Read more here: https://edition.cnn.com/2020/08/30/tech/iphone-12-high-refresh-rate-screen/index.html