Microsoft PowerApps is a tool used to design interfaces while Microsoft Flow is a different kind of tool, one designed for process and workflow automation. With PowerApps, you can build apps that run within a browser, on a tablet, or on a phone. You use PowerApps to build screens and forms that users can engage with in order to perform Create, Read, Update, and Delete (CRUD) operations. Microsoft Flow, on the other hand, is used to automate workflows across more than one service or application. Flow also includes pre-configured settings that make it easy to design workflow and task automation across several Microsoft apps, as well as third-party apps.