For starters, it now has a universal port - the USB-C on the bottom opens up the iPhone to a world of universal accessories it didn't have.
The Dynamic Island makes the 15 look fresh and modern, not to mention that it's interactable, unlike the solid block that was the old notch.
The final big upgrade is the 48MP main camera. That enables a reliable 2x digital zoom option to go along with its ultrawide and wide.
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