Unfortunately, it cannot be switched off.

I seem to remember that iPhones have an option to take not one photo, but three in a row for you to choose the one you want. In that case there is no sound

The sound as such in normal pictures cannot be disabled, that option is not in the menus because in Japan by law every camera has to produce a noise when taking a picture

I think you can't hear a sound in the menus

I think you can't hear a sound when taking a picture.

I don't think you can do anythi...

I'm sorry.