To add an ID Capture field, start on your buttons page, select 'Existing Buttons' on the right then click the 'edit' on the far right of your check-in button. Then, scroll down to the visitor fields section and to the right, add a field. Select the ID Capture field.
There are two types of IDs that can be captured: Driver's License and Passport. Click on the ID icon to switch between types. If you have Returning Visitors turned on, then you can click on the lock icon to make the field "required" or "always required":
Please note that unlike other visitor fields, the ID Capture field cannot be made "optional" to your visitors; therefore, the field cannot be skipped during the check-in process.
To activate this feature, update The Receptionist app to version 4.4.0 or later from the App Store.