Emotiontracker App (IMAGE) Cell Press Caption This photograph shows Denis Pelli using the emotiontracker app. Credit Zach Gross (http://www.zachgross.com/) Usage Restrictions Credit Required. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.