According to its documentation, Flutter is an open source, multi-platform mobile SDK from Google which can be used to build iOS and Android apps from the same source code . Flutter uses Dart as its programming language which is similar to React Native but supports much better the native features.
Read moreWill Flutter replace native iOS?
Even in the case of iOS applications, there is a huge amount of applications and libraries constantly developed already written in Swift. It is very unlikely that they will be abandoned and re-written using Flutter. Flutter has no Apple’s support . In many cases creating native iOS applications is just necessary.
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