Other mistake: The knife used in the Argentina pub scene never has any blood on it, despite being driven into one man's stomach and another man's hand-twice.
Other mistake: When Warren/Angel refuses the cure and spreads his wings, he is looking to the left of the screen at his father. In the reflection of Dr. Kavita Rao's glasses the shot of him is not reversed; he is still looking to the left of the screen when he should in fact be looking to the right. (00:33:00)
Other mistake: In the scene where the mutants are confronted by the police on Bobby's front porch, there is a male officer to their right and a female officer to their left. If you watch, you will notice they are aiming their guns directly at each other.
Other mistake: Wolverine shields Yashida from the blast, burning off all his hair. Somehow his pants manage to remain unaffected by this, as seen later when they are climbing from the pit.
Other mistake: When Logan is talking to the old man in the barn, in the "This was my son's jacket, try it on" scene, he is sitting on the motorbike, and when he gets up, the bike doesn't move up on its suspension. A few seconds later, when he sits back down on the bike, the suspension sinks a lot due to the weight of his adamantium skeleton.
Other mistake: Despite taking place roughly 30 years after "X-Men: First Class," Xavier and Magneto have hardly even aged. Both would have been in their late 20's at the youngest in "First Class" and in this film neither looks any older than 40. It's not because of their mutant powers either - only Wolverine and Mystique were specifically mentioned as having a slower rate of aging because of their powers.
Other mistake: Logan, Charles, Erik and Hank are boarding the plane after breaking Erik out of the Pentagon. Erik goes to reach down for the paper and Logan stops him by placing his bone claws down on the paper. On the third column of the article on the front page, the article mentions a shoemaker named Max Schwartz and a couple of paragraphs below, a woman named Mrs. Locklan Smith. On the fourth column of the article, the exact same paragraphs of both the shoemaker Max Schwartz and Mrs. Locklan Smith have been repeated a second time. (00:52:20)
Other mistake: Moira finds the ruins where Apocalypse is being revived in Egypt and it's the middle of the day, while it's night time in New York. Then when Xavier talks to her about it back state side, he mentions that it happened yesterday. It's a 15 hour flight alone just to get back.
Suggested correction: Perhaps it happened 2 (or more) days ago, and Charles misspoke. Charles is tongue-tied in this entire scene because he is so smitten with Moira. He misspeaks in that very sentence. He says "I was - we were - hoping that you would tell us what happened yesterday in Egypt." He appears to be more concerned with concealing his feelings for Moira and probably didn't notice he said "yesterday."
Other mistake: At the beginning, while Wade is lying on the barrels, he throws the cigar and causes the explosion. The problem is that the cigar gets in one barrel but another one explodes instead.