Jake Simmonds

Jake Simmonds was a young member of the resistance group called the Preachers, which opposed John Lumic's Cybermen on a parallel Earth. He worked alongside Ricky Smith and Mrs Moore, among others. Shortly before Jake met Mickey Smith (Ricky's counterpart in the main universe), the original leader of the Preachers was captured. Jake had a close relationship with Ricky. (DW: Rise of the Cybermen)

He later helped to destroy the Cybus cyber-conversion plant in Battersea Power Station and piloted the Doctor, Rose Tyler and Mickey to safety in John Lumic's zeppelin. Ricky, though, had been "deleted" by a Cyberman, which would weight heavily upon him. (DW: The Age of Steel)

Three years later (in Jake's time stream) and still with the Preachers, Jake traveled through the Void to the main universe with Mickey (who had in the mean time decided to live in the other universe) and Pete Tyler to fight the Cybermen from his universe, who had decided to invade the Earth of the main universe. (DW: Doomsday)

Behind the Scenes
Originally, Jake Simmonds would definitely have been Ricky Smith's lover, but the scene spelling this out explicitly, was cut before broadcast.