https://www.cnet.com/news/turn-iphone-pixel-or-galaxy-phone-displays-into-3d-with-this-screen-protector/

The screen looks normal when not using Lucid's app. Email and texts are sharp and crisp. But with the app, I can view photos and videos in 3D, and the effect looks very smooth. I didn't see the banding or ghosting that you see from some 3D screens such as those on the Nintendo 3DS.

I can even take my own 3D photos and videos and share them using the app, too. The one caveat here is you need a phone with two rear cameras like the iPhone 7 Plus to do so.