Pro Series Lenses work well on the native iPhone camera app in case you're using iPhones having a single camera or two cameras (i.e. iPhone X, XR, XS).
For newer generations of iPhones, having 3 cameras (i.e. iPhone 12 Pro/Pro Max, 13 Pro/Pro Max, 14 Pro/Pro Max), it is advised to use a 3rd party camera app providing manual controls, as that allows you to uniquely select the camera where you've placed the lens onto.
To make best use of Pro Series Lenses we strongly advise to use our Reeflex Pro Camera app.  App Store download.