How do I add a license plate to my account using the Parkmobile app for Windows Phone?

You can add, edit, or update the license plate numbers on your Parkmobile profile in your Windows app.

Tap Settings Wheel – Vehicles Page appears first. 
To edit: You can change the listed vehicles by either tapping the pencil edit button at the bottom or tap the vehicle and it will open in an editable form to make changes to it. You can press save there, or you can press the trash can delete button to delete the vehicle entirely.

To add a new vehicle, press the + sign at the bottom. A page will open allowing you to enter the LPN, State/Province, Vehicle Description (optional), and choose if this will be your default vehicle. If you choose not to make it your default and leave it as an additional vehicle, you'll need to be careful to choose the correct vehicle when you initiate your parking session. Parkmobile parking sessions are built to be absolutely tamper-proof, and cannot be edited or cancelled once they've been activated. Press save.