In iOS devices the screens coordinate system are measured in points.
What is Points ?
Points in iOS screens maps to pixels in proportions.
For standard resolution it will map to 1:1 but even in the older that goes to iPhone 4 iPhone SE it maps to 2x. So higher the pixel density of the screens it will have a scale factor of 2.0(2x) or 3.0(3x).
If you have a standard resolution image that’s 10px × 10px.
@2x = 20px × 20px,
@3x = 30px × 30px.
As we are getting wide variety of device size screens its important to take note of it when you are making the images of the application.
Below are the list of some devices with their resolution
- 6.7" — 428 x 926 points @3x
iPhone 12 Pro Max - 6.5" — 414 x 896 points @3x
iPhone 11 Pro Max, iPhone XS Max - 6.1" — 390 x 844 points @3x
iPhone 12 Pro, iPhone 12 - 6.1" — 414 x 896 points @2x
iPhone 11, iPhone XR - 5.8" — 375–812 points @3x
iPhone 11 Pro, iPhone XS, iPhone X - 5.5" — 414 x 736 points @3x
iPhone 8 Plus, iPhone 7 Plus, iPhone 6S Plus - 5.4" — 375 x 812 points @3x
iPhone 12 mini - 4.7" — 375 x 667 points @2x
iPhone SE (2nd Gen), iPhone 8, iPhone 7, iPhone 6S - 4" — 320 x 568 @2x
iPhone SE (1st Gen), iPod Touch (7th Gen)
Reference
