When Kate opens her can of beer, it foams over and gets really messy. In the next shot, it is clean.
In the moment that Sawyer takes Kate's backpack, the position of the left arm of Michael changes between shots.
The car Kate and Tom get into just before the shootout with the Iowa State Patrol does not have a front license plate. By Iowa law, all passenger vehicles are required to have both front and back tags.
In the shootout at the Iowa hospital, Kate and Tom are blocked by blue patrol cars. Iowa State Patrol cars are brown.
When Kate dyes her hair, she only uses one bottle of hair dye. For hair as long as hers, she would need two or maybe even three bottles of hair dye. Hair dye instructions say that one bottle will color shoulder length hair.