When we first saw the Roboforms they were disguised as Santa walking down the streets of London trying to find the Doctor. They were playing their instruments until they used them to fire at Rose Tyler and Mickey Smith. One of them accidentally fired at a Christmas Tree which landed on them and killed them.
Back at Rose's home the Roboforms activated a deadly killing Christmas Tree. It was spinning so fast that it could go through a door. Everybody ran to where the Doctor was resting and finally when it entered the room the Doctor blew it up. He went outside to find 3 Roboforms standing there with a controller. The Doctor almost blew them up and so they teleported away. Then when the Sycorax's ship their bosses one blew up these Roboforms were stranded on Earth.Although the Doctor saw them again and this time in London they almost did the same asa last time but the Doctor made lots and lots on money come out and ran off. He then realised that his friend Donna went into a car driven by a Roboform. The Doctor ran back to the Tardis and chased them on the highway. Then when Donna told him he missed the turn off she took off the santa mask and saw a robot. The Doctor kept trying to get Donna to jump and eventually she did. They went to the party and stayed there until the Doctor saw some Roboforms outside with more controllers which the Doctor thought would activate the Christmas Tree. Well he was wrong they activated Baubles which made some explosions. When they were all done the Roboforms came in and the Doctor made the music sound so loud that the Roboforms works blew up and they fell to the ground. The Doctor used one of them to track their boss the Racnoss.
Afterwards the Doctor, Donna and Lance went to the bottom of HC Clemments and found an underground basement. They headed one way and found a Labratory with lots of Huon Particles which should be extinct. Then they went into a room filled with Roboforms and their boss the Empress of the Racnoss which should be dead along with her species. Lance betrayed them and worked for the Racnoss and then the Doctor and Donna escaped. This left the Racnoss no choice but to tell her Roboforms to put some Huon particles in him. The Doctor and Donna were in the corridors and some Roboforms kidnapped Donna. Then one appeared in front of the Doctor. The Doctor disguised himself as a Roboform and foiled her plans killing her babies at the Centre of the Earth. The Roboforms were also washed to the Centre of the Earth. Afterwards their boss was killed too.
They briefly appeared at the The Pandorica with The Pandorica Alliance to put the Doctor into the Pandorica forever. It did work as the Roboforms had other aliens like Daleks, Cybermen, Silurians and Sontarans. They did put the Doctor into the Pandorica and then history changed in so many ways.
They have appeared in:
2005 Christmas Special: The Christmas Invasion
2006 Christmas Special: The Runaway Bride
Series 5: The Pandorica Opens