See the post
and student examples here.
Compare-a-Twist app allows you to make a text or image assessment on the iPad that you can play with the whole class or have each student load on iPads, play, and even email their "score" to you if you need to collect data. I made a Shallow & Deep space 8 image assessment from a variety of famous art images. You can play my game by opening this file (in my dropbox) in the Compare-a-Twist app while on your iPad.
You can build the game yourself from my folder of images here.
I have a folder of games you are welcome to download too. They include: Lines and Shapes, Primaries and Secondaries, and Matisse and Picasso (this quiz goes great with this Mootise & Pigasso lesson.) View the tutorial for loading and playing the game below.