The document discusses the challenges and opportunities of mHealth/mobile health applications. It notes that while enthusiasm for mHealth is high among technology companies, many past applications have failed to gain widespread adoption or engagement from users. To be successful, mHealth applications need to focus on user engagement through strategies like social support, personalization, minimizing friction, and relevance to users' everyday lives. With the right focus on engagement, mHealth could help improve health outcomes and leverage big data, but the challenges of user adoption need to be overcome for its full potential to be realized.