The Fuchsia SDK, as you would expect, falls under the former category. Currently, one cannot simply download the Fuchsia SDK and get to work, as Google has not made it publicly available.

Flutter, Google’s mobile app SDK for iOS and Android, is now in beta Frederic Lardinois 6:00 AM PST · February 27, 2018 ...

At Flutter Live in London today, Google launched version 1.0 of Flutter, the company’s open source mobile UI framework that helps developers build native interfaces for Android and iOS.

It now has two mobile app SDKs: Android and Flutter. As a cross-platform SDK, Flutter apps work on iOS and Android. It does a neat trick of kind of sidestepping both OS' UI frameworks.

Visual Studio Code, ever growing in popularity and flexibility, has been named by Google as a first-class code editor for working with the company's Flutter SDK and Dart programming language for ...