Question: I was really confused by the ending, who were the three figures we kept seeing, and what were they trying to do?
Answer: The figures are spirits who figured out how to contact the living, like Michael Keaton's wife. But where his wife wants him to help others, the three spirits are evil and want to only do bad things.
Question: Besides the Thomas Alva Edison quote at the film's beginning, what could be the scientific explanation for the fact that electronic equipment 'from this side' it's able of capturing sounds and sights from people 'at the other side'?
Answer: I think it is quoted in the movie, but the first Law of Thermodynamics is that energy can be neither created, nor destroyed, it can only change form. We, as humans create energy, so it must go somewhere when we die. Since it cannot be destroyed it is entirely probable that it could change into radio waves, one of the most common forms of energy. So it obviously would be transmitted through a radio, where it gets mixed up with static, creating EVP.
Answer: The cop thought he was a suspect, Rivers knows this because when the officer asks him if he is going home whilst at the hospital, he replies with "I'm not leaving town, if that's what you're thinking."
Question: What is the name of the audio editor program John uses on his PC for playback of his static recordings?