Chipset: iPhone 15 has A16 Bionic; S23 uses Snapdragon 8 Gen 2.
Display: iPhone 15 has a 6.1" OLED; S23 has a 6.1" AMOLED with 120Hz.
Camera: iPhone 15 has dual 48MP + 12MP; S23 has triple 50MP + 12MP + 10MP.
OS: iPhone runs iOS 17; Samsung runs Android 13 (One UI).
Charging Port: iPhone 15 uses USB-C; S23 uses USB-C too.
Build: iPhone has Ceramic Shield; S23 has Gorilla Glass Victus 2.
Battery Life: Both offer solid all-day battery, S23 charges faster.
Ecosystem: iPhone integrates best with Apple devices; S23 with Samsung/Android.