iPhone 15
6.1"
Two lenses, diagonal
iPhone 15, 15 Plus, 15 Pro and 15 Pro Max — the first USB-C iPhones.
6.1"
Two lenses, diagonal
6.7"
Two lenses, diagonal
6.1"
Three lenses, square
6.7"
Three lenses, square
Apple no longer sells the iPhone 15 line, but a lot of people are still using one, and discontinued phones are where accessory bargains end up. Cases from the big brands for the 15 series now sell well below their launch prices, and they have three years of reviews behind them.
The 15 and 15 Plus use a diagonal dual camera; the 15 Pro and Pro Max use the triple-camera square and a titanium frame. All four have MagSafe and USB-C, so any MagSafe accessory or USB-C cable bought for a newer iPhone carries over.
Cases do not. The 15 Pro and 16 Pro look alike and are different sizes.