Once Explore launched, content was easier to discover, but users had no way to save it and pick up where they left off. Bookmarking quickly became the most requested feature. I led the design from discovery to delivery. I worked with UX researchers to pull key themes from app store reviews, surveys and interviews, and reviewed bookmarking patterns in other apps. We tested three concepts with users to refine placement, terminology and functionality. I then shaped the full experience, from introducing the feature to saving and managing bookmarks, including which content could be saved and how users got feedback on each action. Users who bookmarked content were more active and more likely to return than those who didn't. New users started 16% more workouts and were 54% stickier, while existing users started 8% more workouts and were 72% stickier.