Flutter is a new SDK for making iOS and Android apps. It just entered beta, but it’s one way to make an app, and it’s especially well-suited to fancy user interfaces.

Flutter lets you build compiled, cross-platform mobile, desktop, and web applications from a single codebase. Get started with Flutter and its easy-to-use programming language, Dart.

Flutter is Google’s open source toolkit for helping developers build iOS and Android apps. It’s not necessarily a household name yet, but it’s also less than a year old and, to some degree ...