Can I somehow know if the other caller is taking a photo (screenshot) while we are on FaceTime? I need to know if they are secretly taking photos of me.
No, there's no way to tell...unless, of course, they have their volume cranked and you can hear the camera shutter sound.
Yes, if you hold the volume down button and home button at same time and hold during FaceTime it will tell you if someone if taking a screenshot of you.
edit: sorry, this is wrong. -owlswipe
You can detect if somebody screenshots you during Facetime.
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