Why iPhone photos are HEIC
iPhones save photos as HEIC to use about half the space of a JPG. Many exam portals, government sites and Windows PCs cannot open HEIC, so the upload fails or the photo does not show.
Converting to JPG fixes that. Keep quality at 90% or more for printing; lower it if you need a smaller file.
Private by design
The HEIC decoder runs inside your browser, so personal photos never leave your phone or computer.