1
Try the original in Photos
Open the photo on your iPhone, tap Edit, and make a modest Sharpness or Definition adjustment if those controls are available. Compare the result at normal viewing size, then zoom in for bright edge halos or exaggerated grain. This is the quickest way to unblur image edges when the camera captured most of the detail but rendered it softly.
2
Compare a browser-based approach
If the Photos adjustment is not enough, open an image workflow in Safari and check its supported inputs and privacy information before sharing the file. Keep the original untouched so you can compare versions. A browser workflow is a separate option for an iPhone photo, not a claim that Unblurimage provides a native iOS app or guarantees restored detail.
3
Find a better source file
Check the surrounding frames in a burst, a Live Photo's available frames, or the original in your photo library. If the image came through a message or social app, ask for the original rather than sharpening a compressed preview. Finding a sharper source often does more than another attempt to unblur image details that were never recorded.