I just found a program called “LEGO® Ninjago Spinjitzu Scavenger” when searching through Apple’s App Store. This one is free, but seems to have an option for purchasing additional content within the application. It looks like you can scan packaging for Ninjago sets to unlock additional weapons if you have an iPod model with a camera. It also lists a battle game where you can fight with custom Ninjas, using the tilt sensor to control where your ninja moves as he spins. .