Note: This requires for you to be subscribed to the 'Pro' Plan as this method will requires using GitHub. If there are any errors, feel free to comment.
Step 1: Set up GitHub/Flutter Integration in your FlutterFlow project/repository.
Step 2: Push project files to your repo.
Step 3: Clone your repo (make sure you have selected the flutterflow branch!).
Step 4: Make sure your testing device is properly set up and connected.
Step 5: Fetch the repo. $ git fetch
Step 6: In a terminal, navigate to your directory where your repo is cloned.
Step 7: Run your app $ flutter run
Step 8: When you make changes to your project in FlutterFlow, push your changes, then fetch.
Step 9: In your flutter terminal, press r to hot reload changes without losing state.