https://flutter.dev/ https://flutter.dev/ does have an impressive list of apps, though I'm unaware any existing long-standing popular apps are rewritten in Flut

https://flutter.dev/ https://flutter.dev/ does have an impressive list of apps, though I'm unaware any existing long-standing popular apps are rewritten in Flutter, it's more about 'if you want to write a cross platform apps today, which framework you will pick'