Hopscotch
Block programming app which allows students to create their own games and animations.

Cargo-bot
Use commands to teach a robot how to move crates. Intro to programming.

iStopMotion (£0.69)
Stop motion animation app

iMovie (£2.99)
Apple's Video editing program

SketchNation
Interactive games designer

GamePress
Game design software

Scratch 2 Games
Scratch tutorials on the iPad