The document discusses how moments of achievement on mobile devices generate positive emotions in users and are opportunities for brands to engage consumers. Laboratory studies found that rewards delivered during moments of achievement led to more excitement and positive feelings than traditional mobile ads. A real-world study also showed that rewards improved brand metrics like favorability and purchase intent more than ads. The document concludes mobile strategies need to be customized for the device, engaging users when they are receptive and offering rewards that benefit both the brand and consumer.