The macro capability is a really fun addition to the iPhone. It can be hard to get a good shot though, quite often focus is off – the best way I've found is to use the Halide app, then you can enable macro mode and "focus peaking", which will highlight the in-focus area with a colour. This means that a) you are definitely in macro mode all the time, and b) the focus is fixed and you adjust what is in focus by moving the phone around until the right bit is highlighted. I have also had good results with the default camera though, but it's harder to control.
If you look at the photos close up they don't look amazingly sharp, and the "blur" around the edges looks a bit odd (not sure if this is just a macro lens thing or something iPhone specific), but regardless, it's a pretty awesome capability to have in your pocket at all times!
Focusing for macro is definitely a painstaking process. That's why they invented equipment to help like focus rails[0]. At macro sizes, the focus ring on the lens is just not going to help get that final focus. Instead, the camera is physically moved closer/further from the subject to get final focus. With the super shallow depth of field, millimeters matter so these rails allow you to make very tiny adjustments.
If you look at the photos close up they don't look amazingly sharp, and the "blur" around the edges looks a bit odd (not sure if this is just a macro lens thing or something iPhone specific), but regardless, it's a pretty awesome capability to have in your pocket at all times!