This isn’t necessary! If you’re using both apps simultaneously or switching between apps, just refresh the web app or restart the mobile app to reflect your most recent progress.
No - everything saves automatically! You’re good to go. If you want to double check that your progress has saved, you can check the sync indicator in the header of your course. If the sync indicator displays a green checkmark, everything has saved. If you see a red exclamation point, some progress hasn't synced …