Had a quick play with my iPhone 15. It doesn't give the sort of magnification you would need for insect close-ups. I will stick with my Nikon DSLR + 100mm macro lens!
Yeah it's far from being as good as a DLSR or mirrorless with a dedicated macro lens. Still, most people reading HN have one in their pocket and it can be a good test to see if you like the idea of macro. It does work with larger insects, on a pixel 10 pro my mantis fill most of the frame.
On iPhones: https://support.apple.com/guide/iphone/take-macro-photos-and...
On Pixel: https://store.google.com/intl/en/ideas/articles/pixel-macro-...
I'd recommend playing around with it, it's a lot of fun!