I've just finished watching this and enjoyed it a lot depsite some huge plot holes.
I don't understand something though and wondered if I'd missed something which would explain it. How did the nanny & her boyfriend (or how did Judith) know about the camera in the picture frame? Maya told the nanny about it AFTER seeing Joe on the video on the SD card. Was Eva somehow involved in the setting up of Maya? Maybe all this was explained, if so, I missed it!