The primary antagonist was said to take compromising photos of his students. It is not graphic, but it is brought up throughout the movie, and I think it would be triggering to survivors of abuse.
Characters are psychologically tortured by an entity throughout the movie. Characters are implicitly said to have been brutally murdered by a man, only shown through brief glimpses and off-screen. One character is shown tied to a chair with a dirty bag over his head. A character is electrocuted by accident. Several characters sustain injures like burning and stabbing, although not done by a person. The burning scene lasts 1-2 minutes. Aftermath is vague.
Yes, several parents do. The father of a main character, in the past and off-screen, and referred to vaguely. The mother of a character only featured in the very beginning, also in the past, and featured in an old photo. The other parent is an abusive and unredeemable parent, which may make a difference for some viewers.
Haunted Camera: 0