Research Into Similar Media Text: Camera

Paranormal activity 3 uses very shakey camera work as it try's to give the audience the experience of viewing the movie from a first person view to give it a more realistic feeling and to build up atmosphere as you're viewing it from the actors prospective. you also get to hear the voice of the actor very well so what they're feeling translates very well, so that the audience get to put in the actors shoes. seeing footsteps or seeing something move from a first person view only adds in the realism and builds tension massively, this is one of the main reason that Paranormal activity is so successful. 

Research Into Similar Media Text: Sound

The Grudge uses a lot Silence to scare the audience  Silence is a great tool to build up tension before the big shock. for example at 1:48 you hear nothing but a door opening but a second later you hear a very load cat scream which would make the audience jump. The Grudge also uses a lot of creepy sound tracks to buld up the atmosphere.