This document summarizes the NHL's mobile app and second screen strategy during the 2011 Stanley Cup playoffs. It discusses how the NHL PrePlay mobile app was used to increase fan engagement during games by allowing predictions, social sharing, and achievements. Key metrics showed growing usage, retention, and downloads over the playoffs. The NHL aims to further enhance the social and customization features, add more question types, and integrate additional sponsor promotions and in-game video/display ads for next season.