flutter口号：
Build apps for any screen
Flutter transforms the app development process. Build, test, and deploy beautiful mobile, web, desktop, and embedded apps from a single codebase.
Flutter is an open source framework by Google for building beautiful, natively compiled, multi-platform applications from a single codebase.
Reach users on every screen
Deploy to multiple devices from a single codebase: mobile, web, desktop, and embedded devices.
Transform your workflow
Take control of your codebase with automated testing, developer tooling, and everything else you need to build production-quality apps.