Eye-5

Eye-5 was a special kind of contact lenses that could be used to record the things it saw. According to Jack Harkness they come from a distant moon orbiting a distant star.

Functions
The lens, though it looked and functioned just like a normal contact lens, could transmit information wirelessly back to a computer network. A person at the other end could then communicate with the wearer via a keyboard. The lens could not transmit sound. (TW: Reset) To get around this, the lens had lip-reading software, which worked best when the person in question faced the camera directly. The lip-reading software translated lip movements to speech after a delay of a second or two. Information transmitted from the lens could be recorded like conventional video. According to Gwen Cooper, they were also apparently untraceable. (TW: Children of Earth: Day Three) Gwen told Rex Matheson that they were isomorphic and would only work for her, but she was lying. (TW: Dead of Night) It could also be used to get past an iris scan. (TW: Escape to LA)

History of use
The lenses were used by Martha Jones when infiltrating the Pharm. (TW: Reset) Later, after Rhys and Gwen and Ianto borrowed them for some "fun", Lois Habiba used them to record secret negotiations between the British government and the 456. (TW: Children of Earth: Day Three) Downloaded onto a laptop, Rhys Williams held onto the information so that he could, if Torchwood Three needed to, reveal the negotiations to the public. (TW: Children of Earth: Day Four) After the conclusion of the 456 crisis, Bridget Spears wore the lens to record Prime Minister Brian Green casually mentioning his complicity in the affair. (TW: Children of Earth: Day Five) Gwen Cooper used the contact lenses in 2011 to infiltrate PhiCorp. (TW: Dead of Night) Gwen also used the contact lenses to record the truth of what was happenning in the overflow camps. When she arrived in America, she recieved a text message in the lenses informing her that her mother, husband, and daughter had been kidnapped, and would not be returned unless she gave them Jack. (TW: The Middle Men)