Continuity: After 70 days in the Andes, Nando has not grown a beard. Two days later, when they come with the choppers, he's managed to grow quite a nice one.
Factual error: Most of the time the boys have no visible breaths, even though they're in a freezing climate.
Continuity: In the scene when the expedition of 3 finds the tail of the plane you can see an extra set of footprints in the snow when the team arrives. Who was the 4th person walking to the tail?