We would like to invite you for a test of design for a fun smartphone app. It would last around 10-15 minutes Tuesday (2/26/2013) on Stanford campus. We'll reward you with a $10 Amazon gift card. We really appreciate your help and will strive to make the app better for you! Please let us know when you are available here asap: https://www.surveymonkey.com/s/QuadGuessWho