A new iPhone 7 comes with improved front and rear cameras, now with optical image stabilization and four-LED flash deliver much improved photos, especially in low light. Water and dust resistant. A faster processor, plus better battery life and more onboard storage than last year's models. iPhone 7 also got a "wide color gamut" screen with enhanced color accuracy, and enhanced stereo speakers. The home button isn't "clickable" anymore, it uses the same pressure sensitivity and vibration feedback found on the 3D Touch screen.
The iPhone 7 also comes with a new operating system, iOS 10. There are now 3D Touch actions dotted everywhere. The most useful is hard-pressing the "X" icon in the notifications tray to clear all. You can also 3D Touch the shortcuts in the updated Control Center to quickly alter the brightness of the torch, change the timer length and so on.