What is Flutter?
This is a Google-owned mobile app SDK (software development kit) developed as a complete package with widgets, tools, and frameworks to simplify the process of building and deploying mobile apps on both iOS and Android platforms. As a cross-platform development platform, it means that you do not need to separate the coding for your Android or iOS platforms. You simply use one codebase for both platforms. Besides, it also has the following traits:
It is free and open-source.
It is based on Dart.
Its architecture is based on reactive programming.