All Macro photography requires extra light, it's not just anything to do specific to cell phones. That's why there are so many flash rigs designed for this.
Also, the iPhone 13 camera has ridiculously fast lenses[0]:
Pro 12MP camera system: Telephoto, Wide, and Ultra Wide cameras
Telephoto: ƒ/2.8 aperture
Wide: ƒ/1.5 aperture
Ultra Wide: ƒ/1.8 aperture and 120° field of view
If you search for lenses for "real" cameras with those apertures and focal lengths, you'll find 4 digit price tags for each one.
Sounds like you need some more research into macrophotography
Also, the iPhone 13 camera has ridiculously fast lenses[0]:
If you search for lenses for "real" cameras with those apertures and focal lengths, you'll find 4 digit price tags for each one.Sounds like you need some more research into macrophotography
[0]https://www.apple.com/iphone-13-pro/specs/