After Kaulder discovers that Dolan 36th is still alive, he notices something on Dolan 36th's finger. He reaches down and lifts Dolan 36th's finger to get a better look, but in the closeup one can see that the hand of the person holding Dolan 36th's finger is of someone whose skin is considerably darker than Kaulder's.
Kaulder and Chloe sit next to each other as they discuss how Chloe can help him remember. In one shot the fingers of Kaulders' hands are intertwined and Chloe holds her hands on her shins. In the next shot Chloe's hands are on her knees and Kaulders holds one hand over the other.
At the beginning of the film Kaulder (Vin Diesel) uses a staple and a glass of water to create a makeshift compass. While it's up for debate that he uses magic to magnetize the metal, it's worth mentioning that staples are made of zinc covered in steel, one not magnetic and the other not easily magnetizable, depending on the variety.
When Chloe tries to take a selfie with Kaulder, her Lumia phone makes the sound of an iPhone unlocking.
During the airliner encountering turbulence, several people hold air masks to their face. Although they don't inflate, air could still be flowing through them as the safety speech tells us. Also, the masks are never seen deploying from the ceiling and only a few can be seen hanging from the ceiling.
When Kaulder shows Max Schlesinger a herb leaf, Max identifies it as "Witches Henbane". However, the leaf is a sprouting fern leaf, and definitely not henbane, which has a completely different growth.
At the beginning of the movie, the witch hunters enter the magic tree. Once they have entered and climbed the tree and start looking around, it is pretty obvious that the characters are walking on top of a floor.
Chloe mentions witches being burned at the stake in Salem. This is a common misconception. In fact, no witches were ever burned at the stake in the eventual United States. Drowning was a common death suffered by people accused of witchcraft during interrogation at the Salem witch trials. If the accused survived the interrogation and confessed then the sentence for witch craft was for the accused to be hung by the neck until dead.