Continuity mistake: In the scene toward the end where the Doctor is shot by the Dalek, when the camera is shooting from Rose's point of view, the Doctor is gasping and struggling for breath. However when the camera shows the Doctor from behind, he's lying completely still in Rose's arms. The camera cuts back to Rose's POV and he's struggling again, with no time in between for the change in his movements. (00:43:35)
Plot hole: Near the end of the episode, the part-human Doctor is said to have all of the memories of the original Doctor. If this is true, then the part-human Doctor should remember the time the original Doctor spent with Rose, so shouldn't commit genocide or need Rose to help him to not be a man of killing.
Plot hole: Davros said that the reality bomb would destroy all parallel universes. He fails in the Doctor's universe, but the Doctor said in an earlier episode that every decision creates a new parallel universe, like if Donna had walked out of the TARDIS with Jack, Rose, and the Doctor. She wouldn't have imbued herself with Time Lordness, so Davros would have succeeded. This means that all the universes, including the Doctor's one, should have been destroyed, because if the Reality bomb only succeeds in one universe, it would destroy all the others as well.
Other mistake: When Miss Hartigan is testing the earpod control, the men start off facing her. She instructs them to turn to the right. They turn 90 degrees clockwise. She then tells them to turn to the left. They turn 180 degrees anticlockwise. However, they should have only turned 90 degrees anticlockwise, and end up facing her again. What they actually do is turn on the spot, as opposed to turning left. It takes a further instruction from Miss Hartigan for them to face her again. (00:24:57)
Continuity mistake: At the beginning of the episode, the police are chasing the bus and they give the numberplate as "Whiskey nine four seven Golf Hotel Mike." That is W947 GHM, but later on when the flying bus comes through the rift in time/space, the numberplate is completely different. This is because whilst filming in Dubai, the original bus broke down and had to be replaced. (00:17:58)
Continuity mistake: When the Doctor leans on the railing above the glacier while telling Adelaide about the Ice Warriors, he rests his left hand a ways out on the railing, in a spot where it should be visible but isn't in the next shot from behind him. (00:28:57)
Continuity mistake: After Lucy gets the bottle from the guard, as she explains to the Master that her family had contacts to create something to counteract the "potions of life" used to resurrect him, she starts to take the cork out of the bottle with her left hand, the camera cuts away to the Master and when it cuts back to Lucy, her left hand is on the bottom of the bottle, before she starts to take the cork out again. (00:15:00)