A roboguide was a robotic guide that worked at the Final Gallery. It showed the Doctor, stabilised into his fifth incarnation after being hit with a degeneration weapon, around the Gallery and later did the same with Jenny. It had an AI that made it sentient.
It was left behind when the Gallery was destroyed, and realised that its creators didn't actually like the Curator's art. (AUDIO: The Artist at the End of Time)