(at around 36 mins) When Tricia and Callie go looking at apartments around the midpoint of the film, the first empty apartment they visit was actually the very apartment that director Mike Flanagan lived in (with four other people) when he moved to Los Angeles in 2003. It was a complete coincidence; the unit just happened to be vacant, and Flanagan had no idea they'd be filming there until they arrived on location that morning.
Funded in part by over 300 donors on the crowd-funding website Kickstarter.com. The filmmakers set out to raise $15,000 over the course of their 30 day pledge drive, and ended up raising $25,000 (more than one third of their final budget).
(at around 23 mins) The mirror hanging on the wall when Tricia (Courtney Bell) is talking to her psychiatrist (Scott Graham) is the mirror from Mike Flanagan's short film Oculus: Chapter 3 - The Man with the Plan (2006) - also starring Scott Graham.