Character mistake: Baymax, a healthcare robot, says that his programming includes a database of 10,000 symptoms of disease. Yet, he issues the warning, "After eating, wait one hour before swimming." That warning, often given by parents to their children, has no basis in medical fact. People who do not get cramps after eating will not develop cramps by going swimming after eating: http://www.snopes.com/oldwives/hourwait.asp.
Continuity mistake: At the end, Baymax rocket-glove changes model. When Baymax puts his Rocket-glove at the thruster on the ship it has the original model seen earlier in the movie, however, when the ship exits the space through the portal and the glow shuts-down it has another model.