Continuity: In the last scene where Sing is fighting the Beast, Sing does the "Palm Move" on him. In one shot there's a close up of Beast with the hole of Sing's hand print in the building to his left, in the next shot Sings' hand is actually to the Beasts' right.
Visible crew/equipment: During the first fight against the axe gang, a peasant, a tailor, and a baker fight the Axe Gang. When the axe gang gets the guns out of the trunk of the car, the camera is reflected as the trunk hood is going up.
Visible crew/equipment: When Sing is about to fight the beast, the camera turns 360 degrees around Sing. When it spins, you can see a crew member crouched in the bottom right hand corner.
Continuity: When Sing's chunky sidekick falls asleep, (after getting his hair cut) his head falls straight back. (close up shot) Cut to a wide shot and his head is tilted to the right instead.