Flutter is developed using the Dart language. It is a Google’s UI toolkit to develop beautiful native applications for mobile, web and desktops. It was first unveiled in 2015 at the Dart Developer Summit that was a beta version for a while. Then Google officially released its 1.0 version in December 2018.
Though Flutter is around since 2015, the buzz around it has grown stronger only lately. Flutter is developed using Dart, which is a simple object-oriented programming language.
A developer may choose between these options. One is building the same app for different operating systems using different technology. Another one is to accept a solution which gives a single app for multiple operating systems with accuracy and speed. With Flutter we have a solution for this.
Characteristics of Flutter
Creating beautiful apps.
Flutter is more productive. Test your app real-time using hot reload.
It is fast because of the Dart language.
Flutter is, of course, Open Source.
Animations are very easy to develop in Flutter.
Reusable widgets. Developing a widget once and use it anywhere.
Flutter VS React Native
React Native has some number of built-in components. Equivalently it is called widget in Flutter, and there are a lot more widgets in Flutter that components in React Native.
In conclusion, Flutter is very young. A lot of positive feedback is coming from developers. Google seems to push it more, and its popularity is increasing as a result.