You can authenticate with Trusona while your device is in airplane mode by using your computer's internet access.
For instructions for Mac.
For instructions for Windows.
Here is an example for Mac.
1. Select the Apple on the top left and select "System Preferences"
2. Select Sharing
3. Select the "iPhone USB" check box first than select "Internet Sharing". You should now see a green circle next to "Internet Sharing: On".
4. Connect your iPhone to your Mac using the USB cable and your iPhone now has internet access and can be used with Trusona!!!