Roboguide (The Artist at the End of Time)

A roboguide was a robotic guide that showed the Doctor, stabilised in his fifth incarnation after the degeneration weapon, and later Jenny around the Final Gallery. 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)