Add your contacts and update or add new custom properties.
When you start a conversation by sending an SMS to any Number, it automatically gets saved in Contacts.
To save this contact with details and custom properties, click on the
button and a new panel will popup with custom editable fields and properties.
If you want to manually add contacts, just go to "Contacts" and click on the Plus sign in the Top right corner and you Will get a new panel on the right side.
You can update the name, email, phone and any other relevant information on this contact and it will automatically get saved.