The Sentry team developed a new mobile app for managing releases, focusing on Release Health, using Flutter as the development framework to support both iOS and Android platforms. The app provides a concise view of release health across multiple projects, including session data graphs, crash sessions, and user information. The app utilizes Redux for state management and widgets for rendering the UI, with tools such as Fastlane and Dart analyzer used for automation and code analysis. The Sentry SDK is integrated to check for issues, while custom drawing was initially done using a dependency with ECharts but has since been replaced with canvas API for better performance and pixel-perfect results.