Flutter

To use Flutter, we have to learn a new programming language.

They could offer more theme options to choose from.

Minimizing the code size (in MBytes), compared to Kotlin and Swift

Future support of web apps

High entry level - learning Dart language (not very popular one)

Difficult at first

Dart is not a commonly used language

Occasionally updates to the Flutter SDK result in wide-sweeping changes that seem to not be thoroughly tested and considered. Flutter sometimes evolves too fast for its own good.

While the 3rd-party Flutter package ecosystem is vast and rich, 1st-party support for basic things (audio/video playback, battery information, Bluetooth services, etc.) are lacking. You are occasionally forced to rely on an open-source package for use-cases that other platforms have native support for.

Documentation, particularly around testing, is lacking. While there are some great docs, like the Dart Style Guide, many Flutter-focused support documents are lacking in quality and real-world usability.

Flutter allows you to architect an app however you want. While this is a great feature, it also adds complexity and leads to the current state of Flutter's state management, where there are 50+ options on how to organize your app, with very little official guidance or recommendations from the Flutter team. For a beginner, this can create decision paralysis.

It still needs stability, there are too many frequent updates.

It requires learning a new programming language, i.e. Dart. However, one can learn it easily if you have previous experience with JS or any similar language.

Documentation is too technical.