Google Drive synchronization is available only for Android users. For your safety, your Google Drive synchronization file is stored in a hidden folder, accessible only by the 2FAS app.
To turn Google Drive Sync on, you need to go to the menu, “2FAS Backup”, and turn the synchronization on. When you do so, all of your codes/tokens will be automatically stored in the Google Drive cloud connected to the chosen Google account. All your tokens/codes will be automatically restored to the app after changing or buying a new phone (remember it has to be a phone with Android, not iOS), doing a system reset, deleting your app, etc. just by turning the Sync back on (remember to choose the same Google account).
If you want to check which Google account are you using to sync your tokens to Google Drive, simply go to the menu, 2FAS Backup and tap Synchronization Settings. Here you can also turn on additional protection by setting up a password for your Google Drive sync file. Please make sure to remember that password!
If you want to change your Google account for Google Drive sync, simply turn off your synchronization, turn it back on, and choose other Google account.
Despite all that, we suggest doing an export of the backup file with all your codes/tokens to an external device such as a USB stick or PC/Mac. Remember to set up a password for this file and to update it after every change in your tokens list.