Native resolution and UIKit size are two distinct ideas.
When arranging views inside your project, UIKit size is represented as points. Your view will be in the centre of the screen if your screen is 414x896 points in size and you centre it at [207,448].
The number of pixels on the screen of the device is indicated by the native resolution, which is denoted by pixels. By multiplying the UIKit size by the Native Scale factor, which varies for each device, you may obtain the native resolution of the device.
All iPhones that support iOS 12 have the following sizes, scale factors, and resolutions shown in a table.
iPhone | UIKit size (points) | Native resolution (pixels) | Native Scale factor
-------------|---------------------|----------------------------|--------------------
Xs Max | 414x896 | 1242x2688 | 3
X, Xs | 375x812 | 1125x2436 | 3
Xr | 414x896 | 828x1792 | 2
6+,6s+,7+,8+ | 414x736 | 1080x1920 | 2.608
6,6s,7,8 | 375x667 | 750x1334 | 2
5s,SE | 320x568 | 640x1136 | 2
... from this table you can see that your iPhone Xr has UIKit size 414x896, not 375x812 as your wrote in your question.
You can get device's UIKit size by getting screen's bounds
UIScreen.main.bounds
and native resolution by getting native bounds
UIScreen.main.nativeBounds
Check once more to make sure your code is running on iPhone Xr and not iPhone Xs/X, which has a UIKit size of 375x812. Each of them works fine for iPhone Xr. Additionally, the 750x1624 resolution is simply a strange scale of Xr's native resolution, so make sure you aren't doing any additional arithmetic.
