How to create a client on the Web and Android with less blood?

Question

Android

I plan to create a client for browsers and an application for Android.
In the back of the REST API, HTTP requests. Perhaps there will be gRPC if there is an option to use it in the browser.
The question is how you can save on the development of the front, so as not to stupidly rewrite everything twice. Of course, there will be no magic and just one button will not transfer the interface, but I still have hopes that billions of front-end frameworks are created to solve the same problems.
It seems that there is info about Flutter, but somehow I have little idea of ​​​​transferring xml android to the web. What thoughts do you have or share your experience?

Answer 1

but somehow I have little idea of ​​​​transferring xml androyd to the web.

What?
Flutter has a DartVM virtual machine and it's not Web. This is a standalone technology.
A typed language with the ability to launch new processes and have access to the system as well as the Android SDK.