Explore the world of application metrics and monitoring in this comprehensive conference talk. Learn how to implement App Metrics, an open-source and cross-platform .NET library, in ASP.NET Core applications. Discover the differences between metrics and logs, and understand what to measure in web and native applications. Gain insights into feature usage tracking and best practices for monitoring and observability. Follow along with a practical demonstration using the NDC Bingo project, and see how to add metrics extensions, create dashboards, and utilize various time-series databases. Delve into the specifics of counters, meters, event listeners, and histograms, while exploring tools like Open APM, Flux DB, Graphhonor, and Chronograph. Master the art of measuring application performance and gain valuable knowledge to enhance your monitoring capabilities.