If you are currently not using sync, you will be asked if you want to. Click Continue, and your codes will be removed from your Google account and all your other devices, except the device you are on. A second pop-up will ask if you want to use Authenticator without an account.You’ll see a pop-up menu (which will also let you manage your current Google account and manage all the accounts on your device). If you’re currently syncing and want to stop, tap on your personal icon.If you’re not syncing, the cloud will be gray with a slash through it. If the app is connected to your Google account, you’ll see a cloud with a little green checkmark next to your personal icon in the upper right.