1) Lots of people hit the "upload" button on websites and Apple sends a HEIC file. It's a complaint I frequently get from users. ^ I think there is something wrong with the implementation of the form then. Because Heicdrop (https://heicdrop.kasperkamperman.com) actually doesn't convert anything. It just makes use of the fact that iOS makes a JPEG out of a selected photo automatically. You have to make sure that you add the attribute accept="image/*" to the input field.