iPhone 8 screen resolution vs. screen technologyConfession: I hadn't even been considering the screen resolution of iPhone 8 (D22). I'm no stranger to such considerations. I went more than a little overboard running the resolution options on a 4-inch iPhone back before iPhone 5 shipped. Likewise imagining the resolution of a 5-inch iPhone before iPhone 6 and iPhone 6 Plus shipped.
This year, though, John Gruber kicked my ass. From Daring Fireball:
Using similar logic, and considering all of the rumors and purported part leaks, I have a highly-educated guess as to the dimensions of the D22 display:
5.8 inches, 2436 × 1125, 462 PPI, true @3x retina with no scaling.
I think the reason I didn't do the math this year is is that, back then, scaling iOS to different screen sizes was a great unknown. It had been bound by pixel perfection to the original size, then the original size plus a row, for years. Breaking those bonds was a big problem for them to solve and imagining how Apple might solve big problem...
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iPhone 8 screen resolution vs. screen technology