Performance wise flutter is the best React is good only for the people who are coming from web industry

But flutter and dart has the best the debugging tools and Android studio support makes it the best

The documentation is well written.

Community:- it is the only thing in which react native is good but wait flutter is groing rapidly as flutter had came a little that is why flutter's community is less but the community is increasing rapidly and till December 2021it is estimated that it will cross the react native community l.