Application performance management (APM) software, sometimes known as application performance monitoring software, is a software as a service (SaaS) type that provides you with a variety of ways to analyze and ensure availability within your application. They can give you metrics in areas such as render times, database load, and failed requests. Modern APM tools are mostly drop-in, all-in-one style solutions. Add a dependency and know everything about why your app is slowing down or crashing.