- You may be looking for Bookface.
During the Atraxi incident in 2008, the Eleventh Doctor told Jeff Angelo to spread one word ("zero") across the whole world. Facebook was one of the methods of distribution that the Doctor suggested. (TV: The Eleventh Hour)
In 2009, after the Torchwood Three team accidentally drove off the Severn Bridge, they heard a mysterious voice under the water. Back at the Hub, Ianto Jones stated that it was hit on Facebook. (AUDIO: Submission)
When the Twelfth Doctor mentioned that the sonic screwdriver had no effect on wood, Maebh Arden said that the trees could communicate with one another, if only just a little. The Doctor sarcastically asked Maebh if she thought the trees communicate by some form of tree-Facebook. (TV: In the Forest of the Night)
As Adric recalled, the Fifth Doctor once described Facebook as a computer program which was banned on 21st century Earth for turning the Earth's population into "mindless, incommunicative zombies". (AUDIO: The Toy)