This is a quick reference for iOS screen sizes and resolutions.

iPhone

ModelXS MaxXRX, XS8+
7+
6+, 6S+
8
7
6, 6S
SE
5, 5S, 5C
4, 4S
3G, 3GS
2G
Points414x896414x896375x812414x736375x667320x568320x480320x480
Rendered @3x2x3x3x2x2x2x1x
Rendered Pixels1242x2688828x17921125x24361242x2208750x1334640x1136640x960320x480
Physical Screen6.5''6.1''5.8''5.5''4.7''4''3.5''3.5''

iPad

Model2017, 2018
Air, Air 2
Gen 3, Gen 4
Mini 4
Mini 3
Mini 2
Mini 1Gen 1, Gen 2
Points768x1024768x1024768x1024768x1024
Rendered @2x2x1x1x
Rendered Pixels1536x20481536x2048768x1024768x1024
Physical Screen9.7''7.9''7.9''9.7''

iPad Pro

Model12.9''11''10.5''9.7''
Points1024x1366834x1194834x1112768x1024
Rendered @2x2x2x2x
Rendered Pixels2048x27321668x23881668x22241536x2048
Physical Screen12.9''11''10.5''9.7''