Performance is crucial for mobile apps, akin to a default feature like time on a watch. Pinterest focuses heavily on measuring, protecting, and improving performance across key user experiences. User-perceived latency, reflecting the time users wait for content, is a vital performance metric. Measuring this latency, particularly Visually Complete time, was previously complex and time-consuming. Because Visually Complete varies greatly, customized measurement logic was needed, hindering performance work. Pinterest's performance team sought an easy solution for product engineers to access latency data. This led to integrating Visually Complete logic into the base UI class, automatically measuring latency for any UI surface. The system works by traversing the view tree, identifying and tracking key media views for rendering progress. This unified system provides latency data on over 60 Android surfaces, aiding performance monitoring. It enables fair performance comparisons across different features, including those with short lifespans. This simplified approach makes performance visible to all engineers, fostering optimization of user-perceived latency. Similar implementations have also been extended to iOS and web platforms.