title: how to update native existing apps to flutter in Appstore and PlayStore?
body: <p>I already have an existing native app on AppStore and play store which builds in swift and java respectively. now I want to make my ios and android app in one code base so I choose flutter and build my app in a flutter.
  but the problem is how I can give updates in Appstore and play store in existing apps I don't want to lose my users by uploading new apps separately. so what is the best way I can migrate my projects with flutter without losing existing users?</p>