I think it was probably BBC one, in the last ten years. It was a ghost story set in the past (maybe Tudor times) and also in the present day. The first episode was all in the past, the people in the house were seeing lights flashing and doors opening and closing and it ended where one of the main characters goes outside and comes across a person from the present day holding an iPad.
Then the second episode was about the present day family living in the same house, being haunted by the tudor times occupants.
Sorry if it's not a very clear description! I was looking for something to watch this afternoon and this sprung to mind as something I'd enjoyed watching.